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Puzzled...

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beorntheold

Registered
Joined
Jan 21, 2005
Hey guys *waves*,


A recommendation from Prime95's STRESS.txt and wonderful first impressions make me think you might be able to help, so here's my story...

A couple of days ago a guy I know formed a folding team and I wanted to join. The f@h console froze my "otherwise stable" machine a couple of times and, after doing some reading, I ran Prime95 to check for instabilities.
It crashes after a couple of minutes at default clocks (133) with every working memory timing :bang head . So I ran memtest. To my surprise it ran okay for several hours at the Probe setting.

Some additional info about my system *points down at sig*:
- running XP Pro SP2 with all updates
- the mobo (bought second hand from ebay a couple of weeks ago) looked brand new - according to the previous owner he used it only a couple of times; the only things I can change are FSB and memory timings; the monitoring doesn't work and I know how to set up MBM - the only readings that make sense are CPU temp (~47-53C) and vcore (stable 1.60V) - all other voltages vary wildly; the vcore reported by the BIOS and CPU-Z is 1.632V - stable; the northbridge used to get pretty hot, so I put a small 40x40 fan on it - it should be ok now.

- the CPU (bought new a couple of weeks ago as well) is a T-Bred "B" 2600+ (16x133) and has been OCed only a couple of MHz, mainly to avoid the feeling that the machine is underclocked, which, as most of you probably know, is a thing the guys from ECS have the habit of doing...

- the PSU (bought new at the same time) is a 550W LC-Power and the voltages reported by MBM on my old mobo were very close to optimal and absolutely stable; the stable vcore on this one makes me think the problem is elsewhere

- the RAM (I've had it for a while)- 2 x 256 Hynix, SPD @ 133 2.5-3-3-6, tested with memtest @ 2-3-3-6

- the video card - a 9800 Pro, bought through ebay, supposedly manufactured by Hercules (has logos and markings on the typically colored PCB that support the theory...) - a week or two after I bought it I saw some memory-caused artifacts and looked at the card more closely - the thermal paste under the heatsink looked like it was applied by a half-trained monkey with it's left leg; the heatsink looked just like ATI's stock solution, but wasn't from aluminum(!?); the 350Mhz Samsung memory used to get so hot that I got scared and changed the heatsink and I run the card slightly underclocked now. I haven't noticed any artefacts since, but I don't really trust the card.

- the sound card (bought second hand through ebay - didn't want to use the onboard codec) - SB Live! ... :attn:

Well, that's pretty much it. Sorry for the novel and thanks in advance for your ideas! :)

P.S. flashing the latest BIOS version didn't help
 
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Welcome to the forums.

This is going to be a difficult one. So here is my best guess. Look for blown capacitors through out the system. When a capacitor is healthy, the top will be flat. When it is not healthy, it will be bulging up. It may have brown goo leaking from the top or bottom.

I did a quick google search and found this. This will give you a good idea of what to look for.

Good luck. Oh, and please consider folding for us. Team 32.

Fold on. Build, Borg, Recruite.


http://www.fozzilinymoo.org/Fozzolog/images/20020419-bad_board.640x480.jpg
 
Thanks for the quick response! :)

Update:

Tried each module individually - rounding errors and illegal sumouts in first Blend test after only a minute or two...

Took the SoundBlaster out - no dice...

Checked for damaged capacitors - as far as I can see there are none.

Small FFTs test ran okay for about 10 minutes then it caused the system to restart. :confused: I'm starting to think that MBM may be right and the BIOS reading is wrong, that the vcore is actually 1.60V. According to my research the board doesn't even have the circuitry to change the vcore per BIOS... and I really don't want to do a pin mod...
 
beorntheold said:
... the monitoring doesn't work and I know how to set up MBM ....


I had overlooked something when I configured MBM... :bang head
Now I have voltage readings. CPU - 1.63V. The Core 1 reading (most likely a 2.5 V line) varies between 1.7 - 3.0 V, pretty unstable. All other readings (+3.3, +5.00, +12.00, -12.00, -5.00) are relatively stable an within limits.
 
Another update:

I think I might have found the problem - under heavy load (Atitool, prime's Small FFT's test) the CPU voltage drops under 1.62V - CPU-Z reported 1.616V...
 
Did a pin mod to 1.70V to compensate. Voltage stays at 1.65-1.66V under load! Prime95 is running TWENTY MINUTES without errors! :clap:

Final update:
f@h console running non stop for more than 14 hours... case closed. :burn:
 
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