AMD 1800XP Tbread limit??

Hi Im a long time reader, finally decide to register myself to this awsome board. I have a AMD 1800 Tbread

AXDA1800DUT3C 9303516270011
JIUHB 0306UPMW

I know my cpu is DUTC not the DLTC so I might be limted. Im running ABIT KX7-333 (version 1.1 with latest bios). I can get 11.5x166 stable. Originally I was using stock heatsink/fan which was running around 50C at idle. No matter what I did, it would not go past 11.5x166 (1910mhz).

I got Thermaltake Volcano 9 but I didn't have any thermal grease at the time and being stupid or brave (or both), I put the fan/heatsink on. It was running fine and I was still getting idle temperature of 50c (running 11.5x166, voltage at 1.60)

Over the weekend I went to a local computer store and bought some type 44 thermal heat sink (made by GC Electronic). This is some good stuff, now the CPU temperature is around 43C at idle running around 4200 RPM and if I run the fan at max speed 4800RPM it drops around 41C (still running 11.5x166).

My temperature seems fine so I did try pushing the multiplier 12x166 and even 12.5x166. It booted fine but it was unstable. I am running 1/5 PCI divider but no matter what I cant push my multiplier beyond 166 (even tried the FAST cpu mode). Could it be my memory (PC-2700 Muskin) that's pushing me back? Some people on Abit forum was running beyond 166FSB even with PC-2700 memory.

Try putting your mult real low and then up the fsb to as high as it will go since you will be taking the CPU out of the equation you will know for sure that it is either your mobo or ram, though I have heard the mushkin makes some pretty solid ram that oc's well. Come back and tell us what you find out.