P4 2.4C - P4P800 oc problem - any ideas?

[JayVee]

Hey guys.

Me and a friend of mine bought exactly the same system. Specs:
P4 2.4C
ASUS P4P800
Kingston HyperX PC3500 Kit of 2 (512MB)
I got a Hercules 9700Pro and he's got a GF4 Ti4200

My problem:
I can't get any further than FSB 255MHz (mem @ 204). I've tried everything (divider 2/3, VCore, VDimm, timings, xtra cooling, one mem module at a time). The last thing I tried is using the TwinMOS 400MHz mem of another friend.
So I set the divider to 2/3 and tadaaa, I got to FSB 270 without tweaking VCore, and 280 with a VCore of 1,6V.

So I tried those very settings with my Kingston. Nuthin! Not even FSB 260 (with mem @ 170 !).

My friend has EXACTLY the same problem.

So we decided to get Corsair TwinMX PC3700, figuring it had to be the mem (incompatible?) since TwinMOS works and Kingston doesn't @ FSB >255 with FSB:MEM 3:2 AND we both had the same problem.

My friend got his mem first. He now can go up to 260MHz FSB, so it's probably the exact situation as before. He's now trying it with the divider @ 3:2 to see whether that helps. However, we want it to run @ 5:4 (of course!).

Any suggestions anyone? Does anyone have this mobo running @ FSB > 260 and a divider of 5:4? Thanx in advance!

 

[JayVee]

Okay, the Corsair TwinX PC3700 runs at FSB 275, but only with the mem divider at 3:2.

Anyone?

 

[boshuter]

I'm running a P4P800 deluxe with 2.6c at 262fsb, 2X512mb Corsair XMS PC3500 5:4 @ 2-2-2-5, it will do a little more with more v. make sure you don't have "turbo" turned on, and try giving it more vdimm voltage.

 

[JayVee]

I tried VDimm 2,85V and it wouldn't help. But hey, the mems running far below spec! Shouldn't be necessary increasing the VDimm.

Hm, it's a little reassuring to finally find someone (yes I have searched...) who has this motherboard (even although I don't have the deluxe - shouln't make any difference though).

Which BIOS are you using? I am thinking about downgrading my BIOS. Perhaps that will help.

 

[Acanthus]

Originally posted by: boshuter
I'm running a P4P800 deluxe with 2.6c at 262fsb, 2X512mb Corsair XMS PC3500 5:4 @ 2-2-2-5, it will do a little more with more v. make sure you don't have "turbo" turned on, and try giving it more vdimm voltage.

what he said.

 

[JayVee]

What do you mean "what he said"? I asked which BIOS he used. And I meant which version, not his settings...

 

[boshuter]

JayVee,

I'm running the 1007 bios right now. I'm going to try out the new beta bios on the asus site real soon. I'm not sure why you are having this problem. I just set my memory to 3:2 w/relaxed timings until I knew what my cpu would run stable. Then I set my memory to 5:4 2-2-2-5 and it's been fine since. Like I said in the other reply, make sure you have the "turbo" option turned off.

 

[JayVee]

Wow, sounds great. Do you have a link for that 1007 BIOS? Can't find it anywhere? Or could you mail it to jayvee!AT!donotreply.com? Thx! And please keep me updatet as soon as you tried the new BIOS.

 

[JayVee]

For your information, I'm quite confident this is the problem:
http://www.xtremesystems.org/forums/showthread.php?s=9d4048c9a0a8d9fd8e563d7ed0bb8434&threadid=17749

Some mobos (or the i865/i875 chipsets alltogether?) don't like to work asynchronously with mem sticks that use Winbond CH-5 chips, which is what Kingston (and presumably Corsair too) uses.

I hope ASUS gets this fixed with their next BIOS, 1010 didn't help.