Mysterious computer hardware problem

This isn’t really the appropriate forum for this, but I wrote it all up and I’m putting it on multiple forums so I figured I might as well try here.

Alright. Long post ahead. End result: I can’t get most video cards to work with my system.

System:
NF7-S 2.0
T-bred B “1700+” at 2 ghz (although I did restore it to default clock during these tests)
1x512mb corsair 3200c2, 1x512mb mushkin 3500
Antec TruePower 430 PSU
Generic, but decent, case.
A week ago, I bought a leadtek 6800 GT 8x agp video card to replace my ti4200.

I put the card in my system, screwed it in, booted up. Everything appeared to be working fine. I began running 3dmark to see how the new card did - after about 2-3 minutes of tests, it started to artifact. It would drop objects or have weird texture glitches… and as time went on, the artifacting got much worse - a minute after the artifacting started, the game wasn’t even recognizable, just a bunch of cubes floating around and stuff.

So I rebooted. Ran again. IIRC, ran fine for a minute, artifacted again, then crashed.

So I reseated the card, made sure the connection was good, screwed it in tight… the exact order of these events may be wrong since it was a week ago, now my POST screen was garbled - random characters and lines on it. By the time I got to the windows load screen, it would be severely garbled and usually crash.

I thought maybe I’d seated the card badly when I adjusted it, so I tried different positions. All of them had weird artifacts, but… the nature of the artifacts would change based on the positioning/tightness of the card. Might have lines across the screen once, and garbled characters the next. So it seemed to me that it was a port/card alignment problem… so I kept trying different screw tensions and positioning to see if I could get one to work.

For whatever reason, holding the card up and back with my hand let me boot into windows and run stuff for a few minutes before it crashed.

Anyway, I ordered an RMA on the card and put in my old ti4200. It worked for a full day, and then, for no reason, with no settings changes or anything, started to artifact and crash.

The artifacting was different, less severe, but it’d still screw things up and crash windows.

So I figured I probably broke the AGP slot when I was tampering with the positioning of the 6800. I took my ti4200 to my friend’s computer to test this (couldn’t test the 6800 there, 4x agp board), and, strangely, the 4200 was glitchy there for just a minute, until I tapped the card, then it ran fine for 20 minutes, playing games, whatever. I’m not sure what to make of that - the 4200 wouldn’t work at all in my system without crashing, but I assumed that the glitching was a positioning fluke and that the card functioned.

I borrowed my friend’s old gf2 mx to test in my system. It ran, and that’s what I’m writing this on now.

So I got a new motherboard. I didn’t want to wait a few days for mail order so I overpaid for an nf7-s2g at best buy. Same board, basically, slightly different layout. I decided to wait till the next day to install it, because the new card from the RMA would come, that way, I’d be starting off with a fresh MB and fresh card.

I have the mb running outside the case now - both to eliminate case alignment problems as a reason for the malfunction, and because it’s easy to swap motherboards and video cards and such. I have it sitting on a static bag, which I assume is okay.

So, now, the two parts that could be broken, the motherboard, and the card are replaced. I fire it up… and… the exact same thing happens. New board, new card. And it still glitches and artifacts on the POST screen and crashes in windows. I try my old ti4200 in the new board, same problem, though less severe. Still, enough to crash windows.

For whatever reason, also, the new mb detects my cpu as a 1.1 ghz cpu. I just left it like that, at default settings. And I couldn’t get the ethernet adapter (onboard) to work. Also, all through this, I’d have some weird lockups at different stages in POSTing, which I’d fix by fiddling with power connectors or video card positioning or whatever. Sometimes the hard drives would power up but the post screen wouldn’t come on, because the video card/agp port seemed really sensitive about positioning

So… I’m pretty confused at this point. Then I noticed something - the ti4200’s fan isn’t powering up. Now… I don’t know that it was before, for all I know, it could’ve been broken for the last 2 years, I didn’t even really notice. But I thought… hey… maybe the PSU got fried when I was fiddling with stuff before, and now the AGP slot isn’t getting enough power. That would explain why the gf2 mx, with low power requirements works, while the ti4200, with greater requirements screws up, but not too severely, and why the 6800, with monster power requirements, massively screws up.

So I go out and buy another antec truepower 430, hook it up to everything, and… nothing changes. Same artifacting. I tried both 6800 cards - the original and the one sent to me due to RMA. They both glitched in the the exact same way. The ti4200 also glitches consistently. The 6800s have a totally garbled screen, with colored garbage ascii characters all over. You can barely recognize the POST screen. The Ti4200 is much less severe - it has a few lines on the ABIT boot up screen, and then the boot up screen data has incorrect characters - looks like typos. Like “Microfofg Wiqdowl U000” instead of “Microsoft Windows 2000”. Once you get to the windows boot load screen, it scrambles pretty bad and crashes. Sometimes hangs, sometimes a blue screen - page fault in non paged area, usually, I think.

So, now I’ve replaced the MB, card, and PSU. The only common components now are the ram and CPU - and if the ram and CPU were broken, I couldn’t be running the system on the gf2 mx like I am now, right?

So I’m stumped.

I plugged in my old MB into the new PSU simply because if they’re both not working I’d rather run the one I liked. Oddly, when I hooked that all up, my old MB detected my cpu as a 1.1 ghz, and gave me some error like about the CPU being unrecognizable or improperly setup. I went into the bios, saved using the old settings I was using (2 ghz) and it booted up fine after that. So maybe there is something up with my CPU - but why am I able to run now if that’s the case?

Anyway, I’m pretty much out of ideas. What else can I replace? What else can I try?

I’m sure you are way past something this basic, but you know that there have been differences in standard voltage between AGP versions? If your board supports 8X then almost certainly this isn’t the problem because I think all 8X is .8 but you might double-check.

Your right the only thing left is the RAM and CPU. It is pretty easy to check the RAM with MemTest. You will need a floppy drive to make is easier. Two weeks ago I had some very severe problems with my computer and after everything else was tried it turned out to be one of the RAM modules. The computer would run but after a while it would BSOD. These memory sticks were running for 2 years prior and one just went bad. I would also reset the BIOS just to rule that out.

My board supports 4x and 8x. If it didn’t, the 6800 wouldn’t have worked at all, not for 5-10 minutes like it actually did.

My first thought when I saw SenorBeef’s setup was “Hmm, RAM from two different manufacturers.”

Beef, try using only one of those memory chips at a time and see if things improve. You may find that one or the other is flakey, or that the combination is flakey.

You can probably fix the incorrect CPU speed in the BIOS setup screen, I’ve had this happen many times (usually when setting up new hardware) - the multiplier or something like that isn’t properly detected and your PC thinks it’s running a slower CPU than it actually has.

I forgot to mention it, but I did try isolating the ram chips. Those chips have been running together fine for months, anyway.

As far as the BIOS - yes, I corrected the problem easily, but it was strange that before, my MB properly detected my CPU, and now it doesn’t. It’s a sign that maybe something is up with the CPU, I guess.

Mine were working together as well. They also were 2 different brands yet one failed. It was the very last thing that was left to check.

Update: Borrowed an old cpu. plugged it in. No change whatsoever in the problem.

So I’ve isolated and tested:

CPU
Ram
MB
PSU
Video card

What else could it possibly be?

I’m wondering if you’ve got a heat or interference problem. The fans on the video cards are working, aren’t they?

As in the OP, the fan on the ti4200 is dead. It tries to spin up sometimes but fails. Not sure how long that has been going on, or the reason for that. It’s certainly not a heat issue if it fails within seconds of being started, though.

The fan on the 6800 works, but I don’t know if it’s underpowered or what. It seems a little low, but I have no basis for comparison. In any case, the heat issue isn’t going to show itself instantly like it does now.