Power On problems with A7N8X v1.6

[ENU291]

(I posted this on the AMDMB.com forums as well)

All,
Hopefully you guys can help me out on this. I have a A7N8X v1.6 and a XP 2800+ proc. I can push the FSB to 200MHZ with a multi of 11.5 (2300MHZ) no prob. When I try 200X12 (2400MHZ) I also have no prob but if I power off the PC completely then power it back on the PC will not POST. If I turn off the PC then back on I get the default 100X12.5 (1250MHZ) message and have to go into the BIOS and make the changes again. What do you people think is causing this?? Once in WinXP at 200X12 (2400MHZ) the PC is 100% stable (ran memtest, prime etc). If I can resolve this power up problem I'll be set.

Details on system:

Athlon XP 2800+
Asus A7N8X Deluxe v1.6 (Uber 1004 with New Serial ATA bios)
Corsair XMS 3200LL (2X512MB-2,3,2,10 timing)
Radeon 9800 Pro 256DDR2
2X SATA Raptor 36GB Raid0
Liteon DVD-Rom
Liteon DVD-R/DVD+R 8X
Audigy 2
Koolance EXOS
Antec True Power 500

[SnakeEyes]

Good luck finding a cure for that problem. I've had similar experiences with my r1.04 A7N8X-Deluxe. I don't shutdown / reboot Windows XP very often (er, except when I'm experimenting with overclocks, which is exactly when I've noticed similar behavior), so it doesn't normally bother me too much.

It's one of those flaky things I've learned to live with on an otherwise pretty good board. (I say pretty good because I reserve excellent for boards with a broader vCore range, 200mhz fsb stability, etc. ;))

[ENU291]

I'm beginning to think that it's time for a new board. I picked up a Athlon XP Mobile 2500+. What do you recommend I pair it up with??

[saturnotaku]

Any Abit NF-7, be it the standard or -S (if you want Soundstorm audio and serial ATA).

[SnakeEyes]

What he said. :D

(If Abit hadn't had a run of bad boards just prior to my looking for an nF2, I'd have one now. Fortunately for you, unfortunately for me, their nF2 boards seem to be top notch. :))

[ENU291]

Just for the hell of it I installed the Athlon XP 2500+ M chip into my A7N8X v1.6 board to see what would happen. The PC booted up with some wacky settings so I made some moderate adjustments in the BIOS (11X166) to give the proc some burn in time. (Uber 1004 bios IDs the chip as Unknown) After a few hours of burn in I started raising the multi and fsb. I quickly found that this chip does not like this board much. It was far from stable at 200MHZ FSB at almost any multipler. :( I figured I'd try 185MHZ FSB to see what happens. 185X11=Good, 185X12=Good, 185X13=Good, 185X13.5=Good :eek: This mobile has legs. :D I didn't go any higher because of time limitations. I left the PC running Prime95 at 185X13.5 (2497MHZ). I'm gonna follow your suggetions and pick up an Abit NF7-S because this board is limiting the vcore to 1.82v. BTW whats the deal with the ABIT AN7? Is it better or worst than the NF7-S for OCin.

[SnakeEyes]

I don't know how the AN7 compares with the NF7. I'd suggest reading the motherboard forums here (http://forums.amdmb.com/) to get a better idea of people's experiences though. These XP 2500+ Mobile processors are monster overclockers, even on these older Asus boards. :)