mikead_99 could be each p4c800-e is slightly different ?

anyway, I did a few changes swapped Gecube X800Pro out for Albatron MX480EL card and put 80GB WD 800JB Hdd on Promise 32bit/66mhz controller instead of board's primary IDE channel and can manage to scrape in a few benchies @ 265mhz 2-2-2-6 at 3.6v

2.8C @ 265fsb
Asus P4C800-E rev2.0 1016 bios
Albatron MX480EL @ stock 275/266
80GB WD 800JB on Promise ATA133 32bit/66mhz controller
550W Antec TrueControl PSU

1:1
2x 256MB XMS3500C2v1.1 BH-5 @265mhz 2-2-2-6 at 3.6v

vAGP = 1.7v for clockgen benched superpi/aida32 and 1.8v for sandra bandwidth benchies
PM = Standard
PAM = Auto
DDR Idle Timer = Infinite
DDR Refresh Rate = 64uSec
Spread spectrum = Disabled
AGP Aperture = 64MB
AGP/PCI = 66.66/33.33
USB Legacy = Disabled

Sandra 2004 STD SP2
Buffered = 6555 / 6550
Unbuffered = 3782 / 3793

Aida32 v3.93
Read = 6468 MB/s
Write = 2026 MB/s
Ram SPD settings

SuperPi
1M = 36s
2M = 1min 25s

notes:
- this ain't 100% stable but working on it
- vAGP of 1.6 was fine if i booted into windows at 233fsb and used clockgen to reach 265mhz 2-2-2-6 and managed run off aida and superpi benchies but trying to boot into windows at 265mhz 2-2-2-6 froze at winxp welcome screen
- vAGP of 1.7v allowed me to boot into windows at 265mhz 2-2-2-6 but mouse and keyboard didn't respond
- vAGP of 1.8v allowed my mouse and keyboard to work fine and run sandra buff/unbuffered benchmarks