- "She'll make point five past lightspeed. She may not look like much, but she's got it where it counts, kid. I've made a lot of special modifications myself."
- Luke Skywalker and Han Solo
In 2002 I bought a Dell Dimension 2350 P4 2.6Ghz PC for my young son. His older brother had a PC, and it seemed right that he should have one too. I didn't know much about PC's at the time and assumed "Integrated Intel Graphics" meant that it might be a bit slower than a dedicated graphics card, but the price was good.
Alas I learned the hard way that if you (or your kids) want to do serious gaming on a PC you need a dedicated graphics card slot , typically AGP or now PCI-Express aka PCI-E. The dimension 2350 did not have one, only 3 humble PCI slots .
Thus began a long and enjoyable exploration of how far I could push this entry-level PC toward serious gaming , and along the way I learned a lot about PC's and have grown to really like this funny old machine. Many, many people have said I was mad and should spend money on a new mother board , graphics card etc. I also have other PC's, some of fairly recent build and performance, but like one of those cheap old cars with all the custom trim, this Dimension has been a lot of fun, even if it makes no economic sense
Almost immediately I found out that many games simply didn't run on the on board graphics, so the first upgrade was to a PCI geforce4 card I bought in panic at Maplin . I found a posting via google of someone who had been through an identical experience and it detailed how to change the graphics adaptor from on-board to PCI in the BIOS. I followed the instructions
I fitted the new card, booted, let windows discover the new second graphics adaptor, made that the default via the Desktop Advanced settings. Rebooted to BIOS and changed the primary graphics adaptor from Auto to PCI.
It worked ! I disabled the on-board and ran entirely from the PCI card which was able to adequately play "X-men: Wolverines revenge" - the offending game which baulked at the on-board Intel graphics chip set.
Thus began the arms race between me and the games industry to see who would blink first. With each new game I have to further tweak the hardware or settings to squeeze a bit more performance out of the old Dell. Here is a picture of the inside of her today, much changed from original.
Over time I'll elaborate on things that have been worthwhile to do, many of which are applicable to any PC. At this point I should introduce a document which I have found invaluable , it's Koroush Ghazi's Ultimate XP Tweak Guide.
There is a good deal of misinformation on the internet about tweaks that supposedly make XP go faster. many are bogus or misinformed, whereas Karoush's guide is well argued and very rigorous . You can obtain the full guide for free , or by making a donation obtain a copy which is print formatted. I printed off a copy and very well thumbed it is too.
PCI is considered fine for most general requirements i.e sound cards, modems, additional USB ports, network cards, but was found to be a performance bottleneck for Graphics and new standards for interconnects were developed (AGP, PCI-express). Many people don't believe they even still make PCI Graphics cards, worse many refer to PCI-E as PCI , lazily dropping the E-for-Express part, unaware of the difference.
PCI Graphics cards are alive and well and continue to be manufactured. They may not have the very latest ATI or nVidia chip sets, but they exist, largely because people still need them toi either run additional monitors or because they need graphics cards for small form factor media PC's which require silent operation and low power requirements.
I have tended to stick with nVidia cards, more out of comfort than any specific reason. The steps below relate to nVidia but I there will be a similar approach to installing ATI-based cards. There are a wide range of ATI PCI cards, the top model currently being the 1550.
I have gone from geforce4 FX440 to a 5200, 5500, 6200 and am now on an Sparkle 8500GT 256Mb PCI card. This may seem insane to a dedicated custom PC builder, but actually it's not. The resell price for old cards, especially PCI is pretty good and I have always got between 50-70% of the original cost back on ebay. Most PCI graphics cards sell from between £25-£50 which is not that much for a graphics card.
the latest card ,which I've only had for 3 weeks is the Sparkle 8500GT 256Mb PCI card. I think this is probably the highest spec nVidia card available in a PCI form factor, though there are ATi cards of similar spec. This card is quite something, being based around a mid range GPU chipset. It's physically large and occupies 1 1/2 PCI bays, so if you use other cards or PCI case fans , you may need to factor this in. It's so thick because of the huge heatsink, so this is entirely passive in it's cooling. It's also a little unusual in that when it was installed XP detected a PCI-to-PCI bridge, so I believe this card implements some kind of PCI-to PCI-E bridge technology. Examining the PC using Control Panel > System > Hardware > device Manager , I can see the card as normal BUT if I use the PCI latency tool it does not see the card, only a PCI-to-PCI bridge device occupying that IRQ. The latency value is also set to zero, as is everything except the network card (32).
I ran the 3dmark03 test on it and achieved a score of 4777, where the previous best card, the 6200 only scored 2011. In gaming too it seems significantly better, my son can play S.T.A.L.K.E.R: shadows of Chernobyl on full resolution and with high detail. Only dynamic lighting has to be disabled, in favour of static lighting, but that's really the icing on the cake.
I try and run the latest drivers from nVidia and the latest version of DirectX from Microsoft. Installing the latest drivers is pretty easy, though I follow a slightly more complex install route, based on Koroush observation that some driver components don't always get correctly updated:
- Download the latest nvidia drivers from the nVidia driver homepage and save to your disk. I also download driver cleaner pro and install that. Don't run it yet.
- Remove the old driver using the Control Panel > Remove Software >nVidia drivers. Don't worry , the PC works OK with no driver. If you rebooted it uses a generic VGA driver. Not as pretty, but you shouldn't be left with a blank screen.
- Reboot into safe mode. I seem to have problems getting the Dell to do this from the boot menu, so while not in safe mode, I first run msconfig from the "Run" option, then select the boot.ini tab and check the SAFE mode box. Later I uncheck this once.s I've carried out step 4.
- In safe mode I run Driver Cleaner Pro to remove any pieces of the nVidia driver left behind. I have also used this approach when updating the SoundMAX sound drivers
- re-run msconfig and unset the SAFE mode and reboot to normal mode
- On reboot XP will discover the graphics card and prompt to install the new driver. I cancel this then run the nVidia driver update
- The nVidia install will run through and may reset the monitor to the lowest resolution. It will also ask you to reboot in order that it can start a number of background processes : 1 a service and 2 via the users start-up tray. You don't have to reboot here, I normally reset the resolution by right-clicking on the desktop background > properties then set the resolution as high as I can.
PCI graphics cards are way behind AGP or PCI-E cards in terms of performance, largely because the PCI bus is the bottleneck and is shared with other devices which in turn, may be making demands of the bus at the same time. There is not a great deal of info on PCI tuning regarding graphics cards, but there is a lot on tuning for sound cards. People involved in using PC's as recording studios sometimes find that their soundcards suffer from lag or 'stutter'. This can be tweaked by modifying the PCI latency, or in other words the time alloted to each device on the bus. In the Dimension , while the sound card is part of the motherboard, it does show up as a PCI device
(Control Panel > System>hardware>Device manager > View by Type).
Another concept to introduce is the IRQ (Interrupt request). Each device in the PC is allotted an IRQ number at boot time by the XP PnP Service, other OS's such as Linux have a similar concept. There are 16 IRQ's (00-15) and so devices typically have to share their allotted IRQ number, as devices include things like the USB interfaces,floppy drive and some of the ports at the back of the PC.
Two concepts worth pursuing in an attempt to squeeze as much performance as possible are :
1) Try to distribute IRQ's evenly i.e don't have CPU intensive devices sharing the same IRQ (Sound, Network, Graphics)
2) Tweak the PCI Latency values to get the best balance
To achieve 1) First you need to look at which devices have which IRQ's using the system tool in control panel. I try to keep Sound, network and Graphics cards on separate IRQ's. But how do you control them ? Well If you are really determined you can override the Universal Plug And Play service, but I prefer a different , safer approach.
First I decided to remove or disable anything I didn't need from the PC. Not only does this free up some room for the PnP service, it also frees up some current for the PSU (see later) and frees up some physical space to improve cooling (also see later). I never use the floppy drive, the only possible use might be if I ever decide to flash the BIOS, but the A01 version I'm running seems to work fine. I could have disabled the Floppy in the BIOS, which would have left it in place should I ever need it. But I decided to open the case, remove it's power and IDE cable then remove the whole drive and frame that supports it below the hard disk. At present I don't have a way of blanking the slot at the front , but I'm not too worried.
Similarly I removed the Modem card, which I never use, which left just my Graphics card as the only device occupying a physical PCI slot.
Next in the BIOS I disabled the floppy drive and I also disabled the Parallel printer port on the back. This PC will never use a parallel printer, most are now USB or better even networked. I also disabled the parallel printer service associated with this
After this if you boot you may see if the balance of IRQ's has been affected. The other thing you can do is move the graphics card to different PCI slots. the affected the IRQ distribution for me, and I found the top slot gave the best balance i.e Sound, network and Graphics on different IRQ's. Some are shared still, typically with USB devices, but this was the best I could achieve.
PCI latency can be examined using the freeware PCI latency tool . I found that maximum latency was being set by my graphics card already (248) and as I was not experiencing any sound lag or stutter symptoms I decided to leave it. I also reasoned that perhaps my network performance might be being affected by the latency dominance of the Graphics card but it was too hard to tell. So I left it alone, but if you are experiencing sound problems and the graphics card is set high, you can use the tool to override this and see if halving the graphics demand improves things. It's a popular and proven mod in the sound card world.
Soon after starting down the PCI graphics card route I also upgraded the memory. The Dimension has two memory slots and can support up to 1Gb. I upgraded to a full 1Gb made up of 2 512Mb PC-2700 simms. I have also played around with the accompanying page file, experimenting with having no page file. In the end I created a dedicated page file partition of 5Gb on my second hard disk and created a maximum size 4096Mb page file in it. I disabled XP recovery mode on that partition. the evidence was that having no page file made no appreciable difference and some large games (i.e. S.T.A.L.K.E.R) might exceed my 1Gb memory capacity.
Based on feedback I received from Robert, I tried 2Gb of memory (2 * 1Gb SIMMS) and the Dell is able to see this in both the BIOS and XP, so now I'm running this machine with 2Gb main memory + 4096Mb page file in it's own partition.
I try to keep the number of processes to a bare minimum, thus maximising the available memory for games by the following :
- reducing the number of services to the bare essentials via control panel >Administration >Services. If in doubt I set them to Manual rather than automatic and see if the server still functions OK
- Ensuring that few if any programs are run at startup. Plenty of software will add something to your start-up when installing. If you ever install something that requires a reboot, its a pretty sure bet that it has either added a service or a start-up script. Sometime these are necessary for the running of the product i.e. Norton Ghost, but often it's just a lazy background update programs. While small they all take up memory and some processing power.
- Checking that no extra tool bars have attached themselves to the browser. I have noticed that various parasitic programs seem to be able to attach themselves to IE in the guise of tool bars. Some are valid, like the google tool bar, others seem to be designed to misdirect your browsing to sponsored sites. I try locking down the Internet Explorer tool bar via it's settings, then checking from time to time what has attached itself using HijackThis
If I reboot the PC , then login, then wait a few minutes for XP to settle I see 18 processes running in Task Manager. A neighbours PC which had some malware problems had 67 processes running. Now some were due to specific graphics or sound cards and were necessary, but you see what can happen.
The Dell Dimension 2350 came with a single 40 or 60 Gb Western Digital drive as I recall. This soon filled up and was supplemented with a second drive a 7200RPM 200Gb Samsung.
Fitting a second drive is a bit of a challenge as the Dimension is quite limited in space,but there are two places you can fit it:
1) In the second tray beneath the existing CDROM drive at the top. This requires a an adapter kit to privide the side runners to slide into to the slot. The Dell had a rounded grey blanking plate on the front which removes to gain access.
2) Piggy backed behind the existing system drive at the bottom of the front. The Dell, like a Compaq we also owned , has the system drive in a vertical position at the bottom front of the case in a metal 'cage'. It's possible to obtain a second metal cage from here, which will attach to the first to add a second bay. This position at the front receives cool air which enters the case via vent holds behind the plastic front piece.
I opted for option 1) and for some time this ran well. However after a while I noticed some 'Bad Block' errors occurring in the system event logs (Control Panel > Admin Tools >Event Viewer > System )- a tell tale sign of a disk going bad. Worse a few related to the main system disk too.
When disks go bad
I therefore cloned the disks to 2 new Maxtor disks which I replaced them with. I used Norton Ghost to do this. Cloning failing drives is not widely recommended on the basis that a copy of a bad drive will be incomplete. Of course the alternative which is to fresh install everything, isn't much better. Interestingly the old Seagate tools had a feature where they would analyse the surface for bad blocks AND reveal the filename of any files affected. This meant you could clone the disk knowing which files might be bad , and make a calculated decision. They might be unimportant i.e temporary files or possibly could be copied from another PC.
To try to avoid this I now employ a number of strategy's :
1) I routinely back up the drives with Norton Ghost
2) I monitor the system event logs for bad blocks or any RED error messages
3) I enabled S.M.A.R.T logging in the disk drives via the BIOS. S.M.A.R.T is a standard way that modern disk drives gather statistics about their performance. This is gathered by the disk and stored within the disk itself. Various tools are available but the data can be quite cryptic.
My favourite tool - speedfan has a tab to display the S.M.A.R.T data in a meaningful 'health check' form, and better still, has a button to compare your disk performance data with others. This is very useful as , for example , it gives a more detailed percentage health measure and how the disk temperature compares with the average for it's type from real users across the internet.
I try and keep the disks as cool as possible and both rarely creep above 30 degrees C (see cooling). speedfan is also able to display the real time temperature of a range of components within the PC including both disk drives.
NOTE: If you ever replace a failing disk drive, you may find the new disk is running slower than expected. This is due to a feature in XP, where, if a drive starts to report errors, XP downgraded the IDE protocol in an attempt to reduce the errors. However , when a new disk is added, it doesn't change back. See a discussion of this on the Microsoft website
It's easy to fix, but may go unnoticed. In my case it manifested it self as general slowness, particularly the number of passes the coloured "pellets" have to make in the XP boot screen. Normally this is around 6-7 but it was 20+ before I fixed this using the above article.
The general consensus as far as I can see, is that Windows seems to favour single large partitions. However I don't, and have my second disk divided up into smaller partitions. For me the greatest weakness with windows is how hard it is to move data and applications around and distribute them across disks. I don't mean drag & drop, cut & paste. I mean "I have a new disk and I'd like to move existing applications and data onto it ". This is easy to do on a Mac, but on windows reinstalling the application on the new drive is the only answer, you'd think it's in everyone's interest including Microsoft's , to make this easier ?
I try to distribute the IO across both disks to achieve some interleaving, especially as my drives are on separate IDE controllers, so I have my operating system (XP Home) on the C: drive and most applications are on the G: drive. In addition I have 2 specialised partitions P: & Z:
P: is a 5Gb partition and only contains the page file. recovery mode is disabled for this partition. No file system files are on it and it's not backed up
Z: is a 5Gb partition and holds all TEMP data. i.e the Control Panel >System > Advanced > Environment Variables that refer to TEMP files all point to this partition , both system and user. Also the IE temporary internet location also points here. It has no recovery enabled and is not backed up. This approach is one from my old Unix system admin days, and it has some advantages. For example this area can get very fragmented, but that fragmentation is contained within this area, so I can defragment this partition very quickly without defragmenting the whole C drive (the default location for all TEMP files). I also tend to download files to this drive and unzip them there. that way my main partitions don't fill up with forgotten downloads and unzips i.e nVidia drivers all get downloaded and expanded here. This drive also has recovery mode disabled, if I lose it it doesn't matter.
I routinely clear out junk from the drives. You can do this via Drive properties (right click on specific drive) which removes recognised temp files and older temporary internet files. I also quite like CCleaner
It not only enables you to analyse and remove all 'crap' from across all drive in a single pass, it provides tools to let you see what programs will auto start (and remove them). Some of it's options can be a bit severe, for example removing recent IE history or recent file open lists, but you can customise it .
I also routinely defragment all drives using the standard included XP tool (right click drive properties), though the TEMP more than others which mostly remain fairly static.
I'd assumed that power supplies required no thought, they just worked and never failed, and if they did , the PC would just not power on.
I have had 2 power supplies fail. One in a Compaq which was conservatively rated at 250WATTS, and one Christmas eve I decided it was the perfect time to attach a 3rd hard drive . This was in addition to a DVD combo and AGP Graphics card. At start-up there was a lot of smoke and a strong smell like the UK Antiseptic 'TCP' ! Worse the Compaq had a unique power supply, so an off the shelf ATX supply would not fit. That marked the end of that particular PC.
the original Dell Dimension 2350 came with a 250watt supply, and this failed but ina a different, gradual way. I noticed that mostly at boot up the CD drive was not there, yet I could add it via 'Add new hardware' and it would magically appear. I thought little of it, but then started to experience random BSOD's and other odd and entirely unconnected types of problems. It was suggested to me that the PSU was starting to fail, so I got a 400Watt ATX supply, which, contrary to much urban myth DOES fit in the Dell Dimension 2350. I didn't give much thought and bought a SWEEX model from my local PC mod store, you can see it at the top of the picture, it's hard to miss in it's full 'bling' gold plating. What I was unprepared for was how much better the PC seemed after ward. Everything seemed fast/quicker etc.
I don't know if the SWEEX unit is especially good, for another PC I got a green high efficiency PSU which consumes less power.
Sites exist which can calculate the total power rating of the entire PC. I think most PC's now come with a 400WATT supply as standard. speedfan is also able to monitor he power supply voltages on some motherboards though not on the dimension.
The new PSU has the intake fan position underneath,and is larger which improves the cooling of the case.
Keeping a PC cool is very important :
1) Components such as disk drives have their life expectancy shortened if continuously subjected to excess heat.
2) The CPU will slow down if it gets above it's operational temperature range. This is a fact, from the P4 onward, Intel incorporated a feedback safety measure, so if you exceed the temperature, the clock slows down. I have witnessed this with a 1.5Ghz P4 Compaq presario which would experience game sound stutter in certain games at certain points. I tried everything, new drivers etc., but could not find a cure. I then found a posting from a French gamer who suggested it was due to the CPU overheating. I downloaded motherboard monitor, which I used before speedfan, and this confirmed that the core CPU temperature was regularly exceeding the maximum for the processor type. In the end the cause was dust "bunnies" i.e. small balls of dust clogging the vanes in the heatsink. I cleared it all out with a can of air duster, then reseated the heatsink with fresh heat grease and the temperature dropped and the game lag disappeared.
3) The noise increases. Some of the fans will regulate their speed with temperature, so a hot PC will have faster fans and generate more noise, which is always annoying.
the classic layout for cooling in a PC is to draw cool air in from the lower front of the case, pass it up over hot components (disks, memory, motherboard) then expel it via a case fan and the PSU fan at the upper back. this assumes a tower configuration. In addition specific "hotspots" have localised blower fans, such as the CPU and Graphics cards.
The Dell Dimension 2350 uses a clever design feature where the case fan also doubles as the CPU fan. A large case fan is positioned on the back, and a large plastic green cowl or hood covers the CPU heatsink. Thus the case fan draws air across the vanes of the CPU heatsink before expelling it from the back. Air is drawn in via various vents at the lower front - to cool the system disk, and via vent holes above each PCI card - to cool the cards.
"If you can not measure it, you can not improve it."
Lord KelvinBefore you can asses the benefits of any cooling measures you have to be able to measure the temperature first. For example I can see that removing the side panel from my PC causes the hard disk temperature to increase . This seems completely illogical as common sense dictates that more ventilation means better cooling ? However, by opening the case you short circuit the wind tunnel the designers have incorporated and less cool air blows across the disk drives. So you see measurement is important.
Most components have on-board temperature sensors which Windows XP completely ignores. Fortunately tools such as motherboard monitor and speedfan are able to extract this data and report on it. I have another PC where speedfan reports the temperature of the CPU, memory controller, 3 disks and the Graphics card and presents this nicely as a gauge on my taskbar.
Alas the Dell dimension motherboard is a somewhat limited here. While speedfan can extract information about the temperature of the disk drives and the graphics card , thus far (up to version 4.34 beta )it is unable to extract the CPU or memory temperature for the motherboard. This may be because the 2350 was built as a cheap model and lacked some niceties, but there clearly is some monitoring of the CPU temperature going on in the BIOS as the case fan speed alters with CPU workload. However I have every confidence that Alfredo Milani Comparetti, the author of speedfan will find way if it exists.
I have fitted round IDE cables to better allow the flow of air as standard flat cables can behave like sails, and block or reroute the lamina air flow through the chassis. I have also removed non essential PCI cards (modems) and the floppy drive. This provides more internal space and airflow.
The second disk drive is in the bay beneath the DVD/CD combo drive and has a coolermaster aerogate front panel fitted. This provides a) a disk fan b) 4 temperature sensors c) the ability to alter the speed of 4 fans and d) a selectable coloured LED display. Initially I used all the temperature probes, but in the end I only monitor from a single probe attached to the CPU heatsink. The fan is useful in keeping the drive temperature low and drawing cool air in the front. The Blue light also looks cool.
I have a Thermaltake A2426 fan located in the slot above the PCI card, which is just a backplate slot with no accompanying PCI slot on the card. Beneath I have a an Azern BlitzStorm double fan occupying the remaining PCI slot below.
All of this means that the Disks seem to stay below 30 degrees C and the GPU peaks at 52 degrees. I may change this to a double blower pushing air at the GPU heatsink
With adequate cooling and a good power supply , overclocking is probably the last area where I can squeeze some more performance out of the Dell. The Dell 2350 motherboard has no overclock capability, but the Graphics card does. Watch this space ....
Update : Have recently upgraded to XP service pack 3, speedfan 4.35 and forceware 175.19
Still running well, with Operation Flashpoint as the game of choice for my Son. the Dell has been plagued a bit of late by the winav.exe malware/trojan thing. It's a trojan which appears to look like a legitimate antivirus tool. It sends all kinds of warnings to the screen, dsiabled the control panel security center and places a red warning in the task tray. AVG free edition did not appear to pick it up, nor did Spybot or windows defender . If had to deal with this sucker twice in the last few months. Perhaps I mistakenly used system recovery to convince myself I'd got the system to a point prior to infection, when in fact it was still there.
Anyway I'm now experimenting with avira antivirus and Malwarebytes, which seemed to do the job.
Generally the PC still works well, but is challenged on newer games. the number of background processes has crept up to around 30 with the extra AV stuff plus an iPod/iTunes.
With current nVidia drivers I'm achieving 5700 in 3dmark03 with no over clock. the latest drivers include the nvida real physics engine, which they aquired through the purchase of Aegis. I have enabled this in nVidia control panel, we'll see if it improves game play.
I have written a separate follow with some further tweaks here
Update : 11/07/2010
The Dell is still going strong. I have switched to Avast for anti virus as this seems to have found a couple of viruses that AVG missed. I was also finding that AVG started a lot of processes.
The PC is used less for games now. My son tends to play games on the xbox360, while the Dell is used primarily for facebook, iTunes and BBC iPlayer, but it keeps on going .
I routinely check the disk health in speedfan, but both hard drives S.M.A.R.T data is within standard operating parameters.
Update : 29/07/2011
the Dell is still going strong. I reverted to Avast free edition for AV, which seems to work well, with periodic running of Malware Bytes. Avast has a nice full scan at boot feature which runs a complete scan prior to windows loading, useful to do sometimes.
The Graphics drivers are up to date from nVidia and the graphics card is still the sparkle 8500.
Recently the audio quality became very distorted, though oddly , only on the right channel. I checked both the front and rear audio connections (green 3.5mm socket) but the same . I reinstalled the SoundMAX drivers, used for this machines on-board audio. Again - no change. In the end I decided to get a Creative external Soundcard X-Fi sound unit, which connects via USB, and provides outputs for 5.1 audio as well as headphones. I toyed with getting an internal PCI card, but the huge graphics card leaves little space. Also the Creative USB card was more future-proof than a PCI sound card, though it did cost more . It works well, the sound comes from a completely silent background, no strange chirps or whistles which sometimes plagued Music when played through the onboard sound system.. There are all kind of effect, for example impressive surround sound effects delivered through conventional stereo headphones
I made sure that I disabled the on-board sound in the BIOS, thus freeing up an IRQ and removing the possibility of conflicts. I used Driver Cleaner Pro to remove any remaining SoundMAX drivers too. Now if I look at the Sound devices in device manager I only see the Creative device and not the SoundMax.
I'll re-run 3dmark again sometime soon and post the results. Possibly disabling the onboard sound subsystem might free up resource ?
I also gave the Dell a good vacuum out internally too, lots of dust had accumulated around the vanes of the main heat sink which would have caused it to overheat. Alas there still appears to be no means of assessing the core CPU temperature with software. I believe the rear fan speed is entirely regulated by a built-in thermistor.
The only issue I'm seeing with the PC is that it takes a very long time to take a user to their desktop from the user picker screen. It sits at the "loading personal settings" screen for more than a minute. i suspect it's waiting for something, which times out then it proceeds. I'll debug what it's doing here when I get more time.
Well the slow loading of settings turned out to be the XP SSDP service which looks for UPNP servers on your network. I don't need this and it probably got enabled by accident. disabling it got the "Loading preferences ..." time back to acceptable.
I re-ran 3dmark03 on the Dell and scored a new all time high of 5317 !!!!!! (I know, a low score on an aged benchmark , but probably appropriate on a PC that's 10 years old )
Not sure if this is due to freeing some resource using the USB sound card ? I doubt it. Actually I noticed that for the first time 3Dmark ran the Audio tests too. previously the on-board SOUNDMAX must have not been recognised by 3dmark. maybe in it's scoring it incorporated some numbers from the 3 audio tests.
Next time I have some free time I'll look at the IRQ spread, now that sound is disabled in the BIOS. I assume that PCI bus contention still is a factor, I'm swapping a PCI directly connected on-board device for a USB connected device, but of course USB also uses the PCI bus.
Update November 2012
Well it is my sad duty to report that the Dell Dimension has now been put out to graze. My teenage Son was finding it was just too slow to get his college course work done on. In the end I succumbed and replaced it with an Apple Mac Mini, which slotted in and meant we could retain the mouse, keyboard , monitor and even the external Creative sound card. His needs are more around internet, music and word processing for college than PC gaming and the Mac was an easy choice.
The Dell never failed, it was just getting slower and slower. I think this was three fold.
1) the number of processes was creeping up. Avast, the external Creative sound card, spotify, iTunes . The total number of processes was in the mid 40's and remember that XP only needs around 18 for you to be up running and connected to the internet.
2) I think the memeo backup software was playing up. It was logging lots of errors for transitory files it couldn't find and didn't need to backup. I perhaps could have investigated this more.
So the Dell Dimension is in my attic. Who knows, perhaps one day to return , in its current guise or perhaps running a flavour of Linux, which might be another way to give it a new lease of life. However I will miss it and it taught me a huge amount about PC's , Graphics cards , XP and doing more with less. Necessity is the mother of invention.