IC7-G/p42.4C stability issues

[SilverSliver]

Well, here's my setup

Abit IC7-G -- new bios, rev 1.1 board
P4 2.4C
Corsair TwinX Platinum PC3200 PT 2:3:2:6 @ 2.8v ( 1 gig dual channel )
Hercules 9800 Pro
Augidy 2


-- Now heres my issue --

Set 2.4C at 250 FSB.
5:4 divider will NOT work.
3:2 divider will work. 250/167 respectively.

Under no circumstance have I been able to stabalize the 5:4 divider. Well...If I run the FSB at 230, and the ram at 180, it is stable but not as fast as the 3/2. I've also tried the 5:4 divider, 250/200 with ram timings of 3/4/4/8 with no luck.

What is my issue here? Why can I not get this ram to reach its STOCK speed rating when I OC the FSB. It seems like the cut off point is around 182 or so for the ram.

And, I have the following in my BIOS tweaked..

PSB800
AGP/PCI fixed

ram bios caches disabled, read and clock disabled under gaming.

-- What else can I do? Im not upping my FSB anymore until I get my Spark 7 HSF in the mail, as I think I could run 280 or so FSB with ram approaching 180, but I'd prefer really a lower FSB with decent ram speed.

What can I do? What am I doing wrong?

 

[SilverSliver]

Please? =(


And when I mean unstable, it boots up fine on most settings, even gets through floating point tests in Sandra, etc.

I bring up 3dmark2k3 and I'll get a syntax error of some sort. Sometimes a lil later, Ill get our favorite blue screen.

 

[RandomTrend]

well for starters you can flash yer bios to the latest...which in your case is 2.0 official...your bios is a lil behind the times...there is where your problems are, more than likely.

you did say the IC7-G right?

another link that has much info
the abit forums (socket 478)

 

[SilverSliver]

I do have the new bios.

 

[Nitro16]

Originally posted by SilverSliver

Corsair TwinX Platinum PC3200 PT 2:3:2:6 @ 2.8v ( 1 gig dual channel )

These are what are causing your problem. They use Winbond CH5 chips, which are notorious for causing i875/i865 boards to hit a brick wall anywhere from 250-270MHz FSB.

 

[SilverSliver]

If the CH-5 chips are the case, why would they be unstable below/at there normal speed rating, but with the FSB upped? 250 FSB 200dRam should be within tolerance IMO.

edit -- Maybe I could convince newegg to give me a new set of ram, different brand and I could pay the difference...maybe some of that new BH-4 stuff when it comes out,this stuff is disappointing that it won't OC well but the timings are nice at 2:3:2:5