Really Strange Overclocking Problem (HELP!)

[vornash]

I have this really strange problem. Here are my basic system specs:

P4 - 2.4ghz (533 fsb) /w ZalmanCNS7000A HSF
Albatron PX845PEV Pro
Sapphire Radeon 9700 non-pro (flashed to Pro, O/Ced to 340/340)
Antec TruePower 380W PSU

Let me first begin by saying, before I began flashing/overclocking my 9700 non-pro, I had no problem overclocking my CPU. Then, I began flashing/overclocking, and suddenly realized I could no longer maintain a stable overclock on my processor. I've tried countless things, but basically I CANNOT O/C my CPU if my video card is O/Ced and visa versa. It's as if they are feeding off the same small amount of power and it runs out when both are overclocked. If I want any O/C at all on my CPU, I must bring my video card down to 290/290 which is almost stock speed for a non-pro. I think it may be my motherboard that is defective, because I've never heard of this type of O/C conflict problem between CPU and vid card. If I overclock CPU and vid card, I simply get hard locks in 3dmark2001 and other games. At 340/340, even an increase of 1mhz on the fsb will hard lock me in 3dmark, but default fsb is perfectly fine!! So annoying! I really need some help.

Here's a short list of things I've tried:

Installed new HSF
Installed new PSU
Increased voltage on AGP slot
Turned off fast writes

 

[OverVolt]

On that Alabatron PX845PEV Pro, i don't think it has AGP/PCI locks so basically when you OC the fsb your pushing the agp/pci out the the 66/33mhz spec. My guess is that as you OC the R9700 pushing the agp bus out of spec makes it crash in games, but when its stock it can handle the higher agp frequency. Just an increase of 1FSB does seem strange though, try playing around with different Oc's on your vid card if you can, and then see how far you can go on OC'ing your CPU.

With the R9700 pro at stock, and CPU overclocked, run Prime95 and Memtest86 to rule out a bad overclock. A 3Dmark2k1/2k3 loop couldn't hurt either. And well, if it won't OC CPU and Vid card then it just won't, and theres nothing you can do about it.

 

[loafbred]

I've read about this same thing happening many times, and I've had to lower one or the other a little to find a stable balance a couple of times. I've never seen a definitive explanation of the cause.