A31p: multiple OS corruption after CPU swap. Confused.

[ajkula66]

So I decided to go from the stock P4M 2.0 (SL6FK, specs here: http://www.cpu-world.com/sspec/SL/SL6FK.html) to a P4M 2.4 (SL6VC, specs here: http://www.cpu-world.com/sspec/SL/SL6VC.html)...

This is not the first time that I've performed this exact swap BUT now I'm running into some really weird stuff...

My A31p double-boots Windows XP and CentOS 6.5 on a Seagate 80GB/7200rpm HDD...

After the CPU swap, the machine booted into BIOS just fine, recognizing the new CPU but failed to boot into CentOS giving "the uncompression failed" error on multiple occasions. So I booted into XP.

The system installs drivers (?), asks for a re-boot, and I follow the suite. Everything seems OK. I run multiple stress tests and the machine seems responsive and well-balanced, except for one thing: it bluescreens - with various codes - every time I open a browser. And that's *any* browser.

Several hours later the machine re-boots on its own, I log back into XP and the system bluescreens within two minutes of the log-on, once again with varying codes shown on the screen.

So I boot PC Doctor for DOS and run multiple tests several times each. CPU, motherboard, GPU, RAM - all pass with flying colours. "Full system load" was also ran on several occasions, and everything tested OK. As did the HDD which - at that point - is in a completely non-bootable state, crashing with a BSOD as previously described.

What I do know:

a) The machine is not overheating. With the "new" CPU temps were in the 50s prior to running stress tests which brought it into the 70s.

b) None of the tests regarding the CPU - be it PC Doctor or Prime 95 - showed any signs of ailment when it came to the processor, whatsoever.

c) The BIOS/EC is the latest one available.

d} The planar is a later, "revised" one which should have no issues running this CPU at all - or at least none of its siblings did in the past.

e) Every single "live" Linux CD/DVD that I attempted to boot failed with the same "uncompression error"...

I swapped the SL6FK back in and the machine returned to its normal behaviour. All is well, from what I can tell, in both XP and CentOS.

What am I missing? Is it *really* possible that something is wrong with the SL6VC but *none* of the tests are detecting it?

Any thoughts/guesses/guidance are appreciated...

[RealBlackStuff]

If all else fails, I happen to have a T30 for sale with the same SL6VC CPU.
Re your e): Booting from a LiveCD with Puppy Linux went without any problems.

[ajkula66]

Re your e): Booting from a LiveCD with Puppy Linux went without any problems.

I'm sure it did...

It's something in this particular setup that went haywire - I'd just like to know what - for the sake of sheer curiosity on my end.

If I don't figure it out I'll just stay with the 2.0 CPU, it's not like this oldtimer is likely to do any heavy lifting ever again...

[dr_st]

CPUs do fail, however rare it may be. And with it being so rare, I would not think it impossible that testing tools will not always detect it.

Testing the CPU in different machine is one near sure way to figure if that is the case.

[ajkula66]

CPUs do fail, however rare it may be. And with it being so rare, I would not think it impossible that testing tools will not always detect it.

I agree. Having said that, I was pretty stumped that it ran Prime 95 for hours without missing a beat.

Testing the CPU in different machine is one near sure way to figure if that is the case.

Agreed again. However, I don't have another P4M system to test the CPU with, so that idea shall be shelved until further notice.

[Norway Pad]

..the machine seems responsive and well-balanced, except for one thing: it bluescreens - with various codes - every time I open a browser. And that's *any* browser.

I have experienced this behavior once, with a 770Z. That machine has the 850Mhz PIII CPU, which is an unsupported upgrade that causes graphics corruption at 1 out of 3 bootups and other random faults. So it seems to me that CPU issues can cause a browser to bluescreen the computer. It didn't happen with XP, but Win2K seems to be unable to run any browser on this machine no matter what I do. No problem in my case, as the 770Z is a collectible. But I always assumed that the upgraded CPU caused this, and I see a possible pattern.

[Pokrzept]

Testing the CPU in different machine is one near sure way to figure if that is the case.

Agreed again. However, I don't have another P4M system to test the CPU with, so that idea shall be helved until further notice.

Currently I'm after nice piece of T30 with an P4-M 2.4 GHz CPU so I'll try to work this out as soon as I get my hands on it Keep your fingers crossed, I'm hoping that price wont go sky-high.

[ajkula66]

I have experienced this behavior once, with a 770Z. That machine has the 850Mhz PIII CPU, which is an unsupported upgrade that causes graphics corruption at 1 out of 3 bootups and other random faults. So it seems to me that CPU issues can cause a browser to bluescreen the computer. It didn't happen with XP, but Win2K seems to be unable to run any browser on this machine no matter what I do. No problem in my case, as the 770Z is a collectible. But I always assumed that the upgraded CPU caused this, and I see a possible pattern.

Thanks for sharing this experience. I have never owned a 770Z and haven't had much of a chance to play with any of the 770 series which were being dumped as "field" machines in favour of T20 units when I first entered my current workplace 15 years ago...

Going from 2.0 to 2.4 is definitely an "unsupported" upgrade on A31p, but also the one that I've performed many a times without any issues. Heck, when these laptops were at their prime some of us used to dump 2.6 CPUs in there and listen to the fan scream as the silicon on the GPU melted...

I might be getting a "plain Jane" T30 sometime soon in a trade, so I'll wait for it to arrive and see how it behaves with this particular SL6VC...until then, I'm back to SL6FK on my A31p, which needed a good cleaning/dusting/re-pasting anyway... ...so all is well.