Pulling hair out...with o/c ing

[sacrum]

Hi all,

Please will someone advise....my setup:

AMD A64 4000+
Asus A8N-Sli Deluxe (BIOS 1004)
Cooler Master Aquagate cpu water cooling
2 x Corsair TwinX 3200 XL
2 x XFX GF6800GT pci-e

Problem:

I'm pretty new to the BIOS settings and am looking to oc current system with FSB:Ram ratio of 1:1 (11X250, Ram at 250mhz) - My current overclock seems to have played havoc with my graphics cards as they will no longer oc by even 1mhz past stock settings! My current oc is 11.5X235 with ram setting lowered but at 235 frequency. This is all at stock voltage.

Something is amiss and I can't see it....what is the best oc for my system (estimation)....I've been through oc guide (very good) but some help would be appreciated as i can not understand why the grphics have become problematic....

tia

 

[TantrumusMaximus]

Is your HTT bus over 1Ghz? What is your HTT multiplier set to, prob 5x? Try 4X at that speed.

Also did you increase your PCI-E from the default 100Mhz because that would play perhaps with the stability of your GPU.

 

[GuitarDaddy]

1. Until a bios fix you can't go over 245mhz ram speed at 1T on the A8N-SLI, 2T is a huge performance hit don't go there. Just keep ram at less than 245mhz.

2. Up the vcore to 1.65 and try booting up at 270mhz x 10 = 2700mhz, HTT=3x, max memclock=DDR333, and use ClockgenN4 to bump the FSB up in windows. And use SuperPI to test for stability
You should be able to get 2.75-2.9ghz

 

[sacrum]

Thanks for help.....Typically I'm away from home and my pc with work! I suspect that
I have not reduced the HTT multiplier from 5x (May be on auto and am assuming its 5 by default) which as TantrumusMaximus suspects, has pushed my HTTbus over 1000 by around 170mhz causing the graphic instability. I've not adjusted the PCI-E from 100mhz.

If I do keep DDR at 1T at 245mhz what ratio should I set the Ram at (1:1 etc)?

so if HTT is at 245z x 3 HTT bus = 735mhz

and if DDR is at 245z x 10 = 2450mhz on 1:1 ratio

is my logic correct?

tia