Sudden overclocking problem

[AstroGuardian]

Hello everyone,

I just encountered a strange problem with overclocking. I used to be able to OC my E4500 with Gigabyte X38-DS5 from stock 2,2GHz (200 x 11) to 3,0GHz (333 x 9) with no problem at all and even 333 x 11 but with increased voltage.

At that time i had my Gigabyte GF 8600GT. After i purchased the Gigabyte GF 9800GT, all overclock attempts failed. Power is not a concern considering i have the Gigabyte OdinGT 550W PSU.

Anyone has an idea hot to solve this problem?

thnx

 

[AstroGuardian]

Additional info: BIOS is F6 latest version. Memory is Hynix 2 x 2Gb DDR-800. I tried fixing the PCI-E frequency to 100 and 110 mhz but no results.
Anyone?

 

[myocardia]

It's very likely because of your PSU. You have a very power-hungry motherboard, four hard drives, and have added a video card that uses ~twice as much 12v power. Since that isn't a very stout PSU, you need to start there with your troubleshooting. Buy a digital multimeter, so you can find out how much your +12v rail droops while you're running 3dMark06. If it's going below ~11.65v (with the CPU @ stock speed), it's the problem.

 

[nomagic]

I concur with myocardia on the notion that the greater power draw may have "degraded" the power output. By the word "degrade," I mean elevation in load voltage deviation, voltage noise, ripple voltage.

The power output could have degraded to the point that the original OC became unstable. However, this is just my speculation. I hope it helps.

Happy Troubleshooting

 

[AstroGuardian]

I wouldn't say that's the problem. On the 12v rail the power draw is 15 amps, and each of the 12v rails has at least 40amps. On total, the computer draws 220-230 watt during 3DMark Vantage.
Another thing is that even small overclocks do not work. For example FSB from 200 to 220 MHz do not work which used to work.

About the PSU not being very stout, my brother has the same PSU + Q6600 + 790 + dual 9800GT in SLI + OC and the computer works just fine. So i don't think that the PSU could be the problem.

I think it has to do something with the PCI-E bus. But what?

 

[AstroGuardian]

come on! Anyone had the same experience?

 

[rogue1979]

Put the old video card back in.

If you can overclock like normal again, it is most likely your power supply.

 

[Big Lar]

I agree with the PSU theory, but just to be sure, maybe run Memtest to rule out the ram..

Larry

 

[AstroGuardian]

It looks like nobody was right after all. I put the old VGA card but it was no go. I did the following while playing more with the bios. I tried to lower the FSB to 133 so the E4500 went like 1.46 ghz. This was the first time the FSB changed since i had this problem. But the mobo didn't want to post. It just kept restarting for maybe 20 times. I unplugged the power supply and the mobo posted at 1.46 ghz. Then i raised the fsb to 266 and cpu to 2,99 ghz. It posted and worked well. After that i raised it even more to fsb 333 x 9 and got 3.00 ghz on the CPU. And it worked flawless.

I did the following to test your PSU theory. with no OC the computer draws maximum 220w while playing FarCry at hight details at 1680 x 1050 with x2 AA. After OC the computer draws 235W maximum under the same circumstances. There was no change AT ALL with the current.

I must conclude that it was maybe a BIOS bug (version F6) and not a power issue.

Thanks all