PCI-E 101Mhz works ?!

[Scougar]

Hi guys,

I am somewhat confused. I was certain after excess cooling of my X1950XT that my card was overheating causing corruption. If I put the fan at 100% with a fan on the VRM's the card started working stably, and not getting the usual black triangles, screaming lines, invisible bits etc.

Now after I have RMA'd it to be picked up tomorrow.... the guys at corsair help (because I have a Corsair PSU that I just bought and was trying to rule out it being that), suggested I try 99 or 101Mhz on the PCI-E bus. Suddenly... the card seems to work, even when on really low fan (standard)... what the heck?

Is this perhaps because really it wasn't at 100mhz but now i've set it to 101mhz it now represents it's 'true' value of 100?

Someone please explain why this works (because I am stunned... well not really, that's PC's and configs for you hehe). But seriously, please explain why if you can

Tried BF2, about to try Obvlion and Stalker (on Ultra high or Maximum) now to see if its Stable.

Matthew

 

[El Jimben]

I have no explanation but I'm sure I've seen in other posts that some people with Conroe setups had issues with their mobos and the problem could only be resolved by upping the PCI-E freq by 1 the same as you have. Tis strange.

 

[helmutcheese]

Same as when you OC, would think you set lock to 100hz but they advise 101 or even 110 for gains.

 

[Scougar]

BF2> Flawless
Oblivion> flawless
Stalker> Flawless (but mad crazy hard disk access for some reason).

Most importantly no corruption, and a quiet(ish) fan. Not even the Sapphire forum of all places yielding results. It took the suggestion from Corsair themselves lol.

Anyway.. cancelling RMA.. VERY happy about it all Will post some scores in a few mins

Matthew

 

[Scougar]

Starting new thread as this will go off topic with results.

Bottom line> Problem solved by setting PCI-E bus to non-standard value of 101Mhz, totally stable

Matthew

 

[gt_junkie]

Same as when you OC, would think you set lock to 100hz but they advise 101 or even 110 for gains.

Yup - run mine at 110mhz.

gt

 

[willhub]

Does 110Mhz increase overclocking then? I was thinking of trying 110Mhz on my setup but am worried it'll fry my 8800gts.

 

[gt_junkie]

At 100 i found it unstable. 110 was the same and i'd heard 110 mentioned on the forums. Used that ever since and been able to overclock happily.

Had my old e6600 @ 3.4ghz with no probs - then my e2160 at 3.2ghz - and now i'm on a new e6600 that can do 3.3ghz @ stock volts so will see how far i can push it once i install some fast ram - using some crucial value at present.

gt

 

[willhub]

At 100 i found it unstable. 110 was the same and i'd heard 110 mentioned on the forums. Used that ever since and been able to overclock happily.

Had my old e6600 @ 3.4ghz with no probs - then my e2160 at 3.2ghz - and now i'm on a new e6600 that can do 3.3ghz @ stock volts so will see how far i can push it once i install some fast ram - using some crucial value at present.

gt

You sure its at stock volts? maybe its set to auto? look at CPU-Z, I gotta do 3.2Ghz at 1.45V, 3.4Ghz is 155V

Is there a risk 110Mhz PCI-E could kill something in my rig?

 

[gt_junkie]

You sure its at stock volts? maybe its set to auto? look at CPU-Z, I gotta do 3.2Ghz at 1.45V, 3.4Ghz is 155V

Is there a risk 110Mhz PCI-E could kill something in my rig?

Yup, was sold to me as a chip that could do up to 3.75ghz under water @1.55v. Saw a screenie at 3.3 with stock volts. I'm currently at 3ghz due to my slow memory limiting the clock. THIS is where i got it from.

As for damage - i've never heard of any. The threads i read when i was looking into it stated it was reliable and effective so i went ahead and did it.

Some people push the PCI frequency gradually - you could try 101-102-103... etc and see how you get on.

gt

 

[simonnance]

You sure its at stock volts? maybe its set to auto? look at CPU-Z, I gotta do 3.2Ghz at 1.45V, 3.4Ghz is 155V

My chip does 3.2Ghz @ 1.325V, 3.4Ghz @ 1.336V.

Then again, 3.6Ghz takes 1.46V!

 

[Scougar]

Any idea why this sorts out the graphics though?

Currently at 2.4Ghz and I know my motherboard limit is about 2.6Ghz. I will try 110mhz see if I can get it stable, as with 101 and 2.6 I get major corruption just like at 100mhz.

I am still baffled as to how graphics corruption is being sorted out by playing with the PCI-E bus, away from the standard setting. Very wierd.

Matthew