Epox 8RDA+ @200mhz fails memtest

[oupei]

before I begin, here's my setup:

1700+ DUT3C @200x11 @1.775v @40idle-45load
8RDA+ @34c
512 MB PC3200 Buffalo RAM (CH-5)
GF4 Ti4200
Maxtor 120 gig 7200rpm 8mb
el cheapo PSU

anyways, I just upgraded my ram from PC2700 and noticed that I am failing memtest #5 at about the 92-98% mark. I've tried all sorts of timings from 6-2-2-2 to 11-4-4-3 but I always fail that test. I was about to RMA the RAM when I decided to test out how it runs async. It failed with CPU@200x11 and RAM@100 but passed with CPU@100x12.5 and RAM@200.

I know this probably means that it's not the ram, but does this necessarily mean it's the mobo? should I be worried about failing memtest, and if so, what can I do about it? I know I can't adjust vdd which is at 1.57~1.58v without modding, and maybe it's the PSU? I dunno. what do you guys think?

 

[Mem]

Have you tried bumping the ram voltage up a little like 2.6v-2.7v?

Cheap PSU could cause problems when overclocking,only sure way is to try a quality PSU like Antec,Sparkle,Enermax etc.

 

[Megatomic]

My 8RDA+ wouldn't go above 197MHz FSB without failing to POST and I couldn't get into windows above 195MHz FSB. You'll probably have to do the Vdd mod on that board.

Have you tried to jack up your Vdimm as Mem suggested? You might try that first.

 

[oupei]

hmmm... my vdimm is at 2.72v by default.

I guess I'll have to look into that vdd mod, but if anybody else has any suggestions...

 

[Peter]

Well, have you tried running the CPU at its rated settings? Overclocking is "at your own risk" for a reason, y'know ...

 

[Big Lar]

If... It is only failing memtest, but running well in windows, try disabling Legacy Usb Support in bios, and run memtest again.

 

[pspada]

sounds like crappy ram, though it could be the cpu. My 8RDA+ runs at 200fsb - but there were heat issues at that speed causing the sound and Lan to be flakey. Once I properly cooled it down, it works just fine.

 

[oupei]

do you guys really think it's the ram?

hmm... but the ram runs fine at 200mhz if I turn down the FSB...

pspada, how hot is too hot for the chipset? I think my chipset temp is in the low 30s. did you do the vdd mod?

 

[Brian48]

My older 8rda (rev 1.1) has never been completely reliable at 200mhz+ FSB unless I use the memory slot closest to the CPU (I think this is slot 1). Slot 3 is only reliable up to 170mhz.

 

[pspada]

Nope, no vdd mod. But I moved the nb heatsink to the sb, and put a Vantec Iceberq on the nb. However there were still times, most often when playing a 3D game like UT2003, when the sound and/or lan would get flakey. So I used a PCI Nic and Soundbastard. but now I've moved to a FIC AU13, and have no problems at the same 11.5x200fsb, stock voltage, using the on-board connections.