Strange behavior

[Shodan486]

So, me and my Abit VP6 are still kicking ass, I am able to run it at 173FSB with no stability issues...under ONE crazy condition - I have to put it on my balcony ...First I thought there's a temperature issue, put some heatsinks on some of the chips, mainly on the ICS chip near the DIMM slots - was frying itself quite much...but that didn't help anything. So I decided to perform ''collateral'' cooling, thus putting it outsied where it was like +2 degrees Celsius.

CPUs - 15 degrees
HDD - 14 degrees
GPU - 50 degrees

I am able to play anything stable as long as it is in this environment. BUT

I put it back yesterday to my living room and tried to OC it back to 166MHz which runs absolutely stable. But guess what - I cannost OC it again even a MHz above of 153...Don't know what happened.

So my question is (thinking that all of this may be somehow connected to the capacitor's chemistry) - Is there some chemical reaction when a cap is stressed at lower temperatures and then suddenly used in a typical room temperature environment?

I'll get back home soon and turn it on at the 166MHz, let's see what it does.

[kaniki]

Re: Strange behavior

how is the power supply. Maybe the power supply is being stressed and the extra coolness of outside is keeping it cooler then in the house which is giving a more stable voltage.??

The other thing that i can think of is maybe the heatsink on the processor. do you have good heatsink paste on it to make a good connection for heat transfer? maybe the processor is overheating slightly which is causing the problem?

[Shodan486]

Re: Strange behavior

how is the power supply. Maybe the power supply is being stressed and the extra coolness of outside is keeping it cooler then in the house which is giving a more stable voltage.??

The other thing that i can think of is maybe the heatsink on the processor. do you have good heatsink paste on it to make a good connection for heat transfer? maybe the processor is overheating slightly which is causing the problem?

The power supply is a Blue storm II 500W, I highly doubt it would be the cause, yet I will test a Epsilon 700W just for the sake of it. Maybe you're right with the cooling outside...hope somebody would say something to this.

The CPUs have been tested with & without the paste and the coolers are vey good, polished thoroughly...

[mockingbird]

Re: Strange behavior

At 133mhz your pci divider is 1/4, at 166 it is 1/5. You need an AGP divider of 2.5 so that your videocard can run at 66mhz.

Did it occur to you that you might have stressed one of the PCI components (Which includes onboard devices) or even the videocard and that is what might be setting up your wall?

Depending on how you ran things (i.e. if your an them out of spec - which you did because you've indicated that you've tried nonstandard FSBs), you might have stressed something out and it will be like a needle in a haystack finding out exactly what.

If you've been playing with the CPU Vcore the data pathways in the chip might have degraded over time when they are overvolted. (This was well documented back in the days of Mendocino and especially Northwood overclocking. The Mendocinos would start to overheat, and the Northwoods would die completely). Are you overvolting your chip by much?

There used to be a Korean on eBay who sold Pentium III-s 1.4 self-modded CPUs. I don't know how well these worked, or if these worked in SMP (But they should, they're designed to) after doing the mod, but you could buy them for $10 a piece.

You can get two of those running at 133mhz FSB and you'll have no need to overclock.

Unless, that is, you were overclocking specifically the ram for more bandwidth which if I may say is a futile excercise when you have a VIA chipset bottlenecking you anyways :-p

[kaniki]

Re: Strange behavior

well the overhaeted parts might be it.. he did say

put some heatsinks on some of the chips, mainly on the ICS chip near the DIMM slots - was frying itself quite much...but that didn't help anything.

if you already fried something then it would not help.. but who know's

maybe your bios glitched out too. try resetting the bios back to factory.. not through the bios but by the reset on the motherboard.. jumper, remove battery, etc..

[Shodan486]

Re: Strange behavior

See below

[Shodan486]

Re: Strange behavior

To Mockingbird - VIA chipsets provide (in those times) quite excellent choices to tweak number of options, I agree that the bandwidth is not so good, but set it up correctly and you can beat some of the other brands. Mainly AGP driving strength and its values are the greates benefit, which I have not seen in a BIOS on an Intel chipset. Of course Intel chips automatically set the best value, but sometimes it's not the best .

In regards of the 1,4GHz CPUs, those are Tualies, which cannot run both on this board, even when using the powerleap adaptor. Please, prove me wrong.

I wasn't increasing the Vcore value, only the VCC3.3, but this counts only for the motheboard - PCI & AGP bus, DIMMs and maybe the rest of electronics. I was looking at the diagram and it has some VCC, but nothing seems to be pointing towards any 3.3v voltage, only VCC1.5 & 2.5.

I will have to get out all the unnecessary HW to see if I find the needle in my haystack , that's all I can conclude.

But back to my question - any chemical reactions possible within the caps under these circumstances?

P.S. - well, I guess if it was already fried, it wouldn't run stable at 150mhz, even that's ''out of specs''. It wouldn't run at all.

[370forlife]

Re: Strange behavior

You are stressing that blue storm II also, that only has 152W on the 5v and 3.3v rail. For a setup like that you need something like 200W or so combined on the 5v and 3.3v rail. Epsilon 700W only has 155W on the 5v and 3.3v rail.

Stressing the minor rails on a 12V based psu can really hurt the lifespan.

[Shodan486]

Re: Strange behavior

Yes, I was really trying to suspect the power supply...Well, I guess I can try that out...

[kaniki]

Re: Strange behavior

P.S. - well, I guess if it was already fried, it wouldn't run stable at 150mhz, even that's ''out of specs''. It wouldn't run at all.

I did not mean it was totally fried, i just meant that if it was partly damaged, that it may not run the way that you were trying to set it up. I had a friend that overheated her CPU. It ran unstable at its rated speed, but if you lowered the speed down a notch, then it ran stable with no problem.. partly fried but not completely.

[acstech]

Re: Strange behavior

It has to be on the balcony? If you return it there will it work correctly? If it does, I'd say look at the electrical environment. Are you plugging it in to the same outlet? Do they both deliver the same voltage? Some power supplies do react to changes in input voltage. If your PSU is suspect, then a small change could change your OC ability.

That's what it sounds like to me.