Problems with overclocking the athlon XP 2500+

[imported_Stingray]

Hi all, i recently began wanting to overclock my CPU FSB a bit further (perhaps to increase general and gaming performance).

Anyway, at the moment its clocked at 12.5 x 178mhz (2225mhz) with a Vcore of 1.675V (up from 1.65V in order to run prime95 stable for 4+ hours)

All in all, i can say i have gotten a pretty good CPU specimen- being able to clock to 2200mhz from 1800mhz without any Vcore change is pretty good, imo.

My ram is not as good, however- its a gig of pc3200 "Nanya" ram using elixir modules rated at 8-3-3-3 performance at 200mhz.

My motherboard is the a7n8x-x, and i think it is the source of my problems.

Anyway, whenever i try to set the FSB up to 185mhz, regardless of my Vcore, CPU external multiplier or Ram Voltage, my computer fails to boot windows. For me, this pretty much isolated the problem with the motherboard, but how could this be- the motherboard is certified as an nforce2-400 chipset, advertising its capability of 400mhz FSB...

No matter what CPU_FSB jumper setting i change it to, nor what BIOS i flash it to (tried the stock 1004 bios, the 1010 bios (latest), and the custom "UBER BIOS" 1005).

Could it be that i didn't flash the BIOS properly due to using the built-in ALT-F2 awdflash method, rather than doing it from the harddisk? Reason being, many others report higher FSB overclocks when using the UBER BIOS, however i get exactly the same results- fails to boot from an fsb of 183 onwards, regardless of mem timings, voltage, cpu multiplier, vcore....

Anyway, i guess im beginning to be resigned to a life of 178mhz FSB...which is a pity because i picked up a zalman 7000B-Alcu heatsink just for overclocking (currently idling 30degreesC, load is around 40-45degreesC according to MBM5)

Please, anyone with any experience with overclocking the 2500+ or the a7n8x motherboard, post away!

Thanks in advance

 

[imported_Stingray]

Also, i highly doubt its an issue of the northbridge getting too hot- i changed my case and added the 7000B which dramatically decreased ambient case temps (better exhaust, and the 7000B helps to cool the northbridge), however NO change in overclocking performance, at all...

[EDIT]

Also, does it mean anything if i am able to clock the CPU at a 200mhz FSB after setting up a ram divider? (ram works at 166mhz), or does this also limit the bandwith of the northbridge, hence not isolating the problem to the ram? I would think this is strange as the ram is able to hit 10-2-2-2.5t at stock voltages at 178mhz and not do 10-3-3-3 at 2.7V at 185mhz...

 

[imported_Stingray]

PROBLEM SOLVED!!!

Turns out that i had my pair of ram sticks in the 2nd and 3rd dimm slots- putting them in the 1st and 2nd slots afforded the added stability, and now i can boot with FSBs in excess of 185mhz!

I wish the motherboard manual mentioned that ram sticks should go in the first and second slots before the third for stability...anyway, running @ 3200+ speeds atm rock solid, and couldn't be happier about it.

Sorry if i wasted your time!