p5b deluxe + e6600 + ultra120 cooler

Ulfbersark

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my ram is ocz pc2-8000 1000mhz made for 5-5-5-15 timing

I can boot at 4 gigahert overclock (445fsb w/ 9x multiplier) and having tempatures around 50 celc. But windows fails to start. Blue screen of death ranting about irq problems. I've tried this with various voltages (ranging to max) and the same thing. I can get into windows at 415fsb however it will bluescreen me within seconds of running prime95s torture test.

I assume the problem is with the motherboard, as the northbridge chip starts to burn to the touch. I would estimate the heatsink at 90celcius. Even though the mobo monitor says 35celc. I remember reading somewhere where they put the sensors in weird places.

If I bought a mobochip fan, would it solve my problem?
Or more 80mm fans blowing across the mobo?
 

Ulfbersark

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Providing you don't use more than 1.55V vcore the heatsinks on the MOSFET will do just fine with the air from the CPU's HSF.

What you need to do now is remove the entire heatpipe cooling, clean it and replace with thermal paste. Hopefully you would've noticed the ASUS logo plate stuck on by glue and is very easy to remove to expose the fins/pins.

I personally prefer a 40mm fan screwed on top of chipset heatsink, looks tidier that way. A 80mm will do as well as long as it's relatively close the heatsinks and gets the air forced in between.

That's about all you need to solve the cooling issue and should be able to maintain higher than 445Mhz FSB no problem.

Have fun and good luck! :wink:

Thanks a lot. I know *generally* what you are referring to by MOSFET and HSF, but what exactly do those letters stand for and where could I find them on the mobo?
 

Ulfbersark

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Allright got a fan on my northbridge.

This is very strange though. I still have the same problem.

So I figured it may have been a voltage problem, so I left the voltage settings the same (highest possible) and clocked it back to 350fsb (where I run stable).

Runs hot, but sure is just as stable.


I can't understand why 415-445fsb becomes unstable.

I set the cpu vcore to 1.7v and it shows only ~1.64v when booted up.
I am assuming this is normal.

But, is it possibe, at the highest voltage settings across the board, that it isn't enough for 415-445 fsb?

: (
 

Hando567

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no that voltage would be plenty in fact id go as far as saying its way too much. you want to bump it to maybe 1.4-1.45 id guess and for only 350 definately no more than 1.4. and 67C is HOT like way too hot.try lowering your vcore. dont know what other voltages are. make sure your VDIMM is atleast +.3 V as that would be 2.1 which is about right for your memory i think need to check to be sure though.
 

Ulfbersark

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While i'm trying to figure this out, on a side topic - how do you run dual instances of Prime95? Doubleclicking the icon doesn't seem to work : / ;p
 

Ulfbersark

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im currently having some problems with what seems to be a defective xtx 7900gt. tuning down my overclock seems to help, not sure why. perhaps decreasing voltage to the pcie helps to decrease heat.

so i'm not sure i can give these results until i get an rma and see for sure.
 

Ulfbersark

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haven't seen another pcie voltage option, and havne't set it above 100mhz.

It's strange. If I decrease the SB voltage to default, but run at 3.6mhz. I get much more artifacting than if I run the e6600 at stock 2.4ghz.

How does the fsb affect a video card?


I believe the video card may be limiting my overclocking potential, and that it may be the reason for instability at higher clocks.

Maybe I can try this if I find a pci vid card somewhere.