Lockups, sluggish and choppy

Question

My name is Neal and although i'm a computer technician i've had the biggest problems of my life with this machine. I started out with these specs:
Athlon XP1900+
512MB Crucial 2700
WD Seagate 80GB
MSI KT4V-L
MSI 128MB Ti4200 4x
Turtle Beach Cruz
430W Antec Truepower
Win XP Pro
I was getting very sluggish 3D performance, often everything was very choppy. My first instinct was that this was a RAM fault, and so i borrowed a stick to test it out, same problem. I ran 3DMARK for hours to see how my Ti4200 was performing. I could easily get well over 11000 points, very happy too, but when it came to playing a game i was back to the choppy performance.
My next thought was IRQ's, they checked out OK but i removed my sound card from the system to see how that figured. Still the same problem. I then clean installed windows again, still no joy and so i pointed my finger at a dud motherboard.
I went out and got the Delta-ILSR and started all over, and guess what shock horror, i was still getting the same crappy problem! And because of all the problems people have with incompatible memory i decided to steer clear and buy some mushkins.
It was time to check out this VGA card. I temporarily bought a 9800 Pro and stuck it in, slight improvement, no as sluggish but still a little choppy. But to add even more insult to injury my PC now locks up if i play for more than 15 minutes. I think that could be the summer heat, but i opened up the case, blew a 30 inch fan over my board and it still locked up. X(
I've tried all the obvious things i could think of; drivers, BIOS, IRQ's, Memory conflicts, fastwrites, SMART.... but i still can't figure this out. :O
So after all that my current machine stands at:
Athlon XP 2800+
512 Mushkin 3200
WD Seagate 80GB
MSI K7N2 Delta-ILSR
ATI 128MB 9800 Pro
Win XP Pro
Antec 430W
Any help would be much appreciated. I've never come across a machine quite like this one. I figure it must be a foul setting somewhere, but  ?(  ?(  ?(
Neal

Answer 1

OK at the moment i'm set up as follows:
XP 2800+ 166FSB (Coolermaster silent copper heatsink/fan w/arctic silver 3)
1x512MB PC3200 Mushkin level 2 (slot 1)
40GB WD (7200RPM 8MB Cache)
Panasonic DVD-Rom
Sony Floppy Drive
ATI 9800 Pro (Aperture 128MB)
MSI Delta-ILSR (AC97 Audio enabled, all other onboard devices are disabled)
Truepower 430W & three system cooling fans
PS/2 Keyboard and Mouse
IIyama Pro 415 @ 1024x768 100Hz
Win XP Pro SP1
The problem has been the same throughout and i have replaced all my pieces of hardware at least once. All my games lag, stutter or whatever you want to call it. Some games are worse than others. Older games like Unreal Tournament tend to have no problems, i'm guessing this is because they need almost no 3D support, whereas newer games like Vice City, Nightfire, Jedi Knight 2 tend to be quite bad. UT2003 isn't too bad and is playable. Nightfire i would say is the worst and so i always use that game as my test game.
Theoretically i'm performing well. 16000+ points 3DMARK2001SE. PCMARK claims my CPU, memory and HDD work well. Memtest86 showed no errors after almost 3 hours of running the test.
Some videos i notice have lag as well and that can be resolved by disabling my soundcard. This however does not work as a solution in games. IRQ's all seperate, DMA modes are all correct. I installed my drivers according to the recommended nForcer's guide. Seems there is no issue there but i cannot be certain.
To me it looks like a bottleneck issue, the videocard is never getting the juice it needs, which i can hardly believe running under a True430 and a UPS for backup. But what i said before about games that don't need much 3D rendering work well, older games, seems to support my assumption.
The other possibilty is my memory. I've got 3 sticks of memory, no improvement between the sticks or between the slots i use in this mobo or my previous one (VIA chipset). So i can't realistically assume that.
See what you can make of that,
Thanks for helping out,
Neal