crashed win2k w/ AT7 & 1700

Hey All,
I am somewhat new to oc'ing amd and I had a few questions. I am trying to see how high i can get this 1700. I was running stable for over a month at 195 @ 11.5 but I wanted more so I cut the multiplier down to 10 and started cranking up the bus. I was doing good til I hit 206 then it went to hell. I have it locked at 5.2.1. My video was all funky so I cut it down to 200 but by the time I started to reboot I crashed windows and it kept going to a c: prompt. Did this happen because my vc crapped out on me or ??? What should I do different to achieve a higher oc.

Here are my specs:
Abit AT7
1700 xp w/ Zalman CNPS6000
512 PC3200 Corsair XMS
128mb Radeon 8500LE
431W Enermax

Please let me know what you think and if I am forgetting anything.
THANKS!!!

How much vcore are you giving the cpu? Maybe you're not giving enough. That heatsink you're using isn't very good for overclocking too unless you're using a really high speed fan.

the vcore is at 1.75 but I don't think that is the problem because i had it clocked at 195x11.5=2242 for over a month and I had no probs. I think it was my vc because once i started cranking the fsb the video got messed up and windows crashed...