Overclocking seems to prevent Vista from booting?!

Im running an Asus M2N32 SLi Deluxe mobo with AMD X2 5200+, asus silent knight cooler,2gb ddr2 800 ram, 2x leadtek 7900gt, creative x-fi fata1tyand a 580w tagen psu, NZXT Lexa case. (windows vista home premium)The odd problem ive had was after id bought my new cooler (the stock cooler is pretty pathetic) and installed it all, i booted the pc up to check id got everything plugged in properly as i had to take the mobo out of the case to fit the cooler, and everything ran fine.So i thought now thati have a better cooler ill give it some overclock, so from stock speed of 2.6ghz i tried it at 2.7ghz, and windows wouldnt boot, my old installation of xp would, but not vista, it got to where the green bar moves across and that flickers then restarted the pc. After much annoyance and fiddling with settings i finally got it to work after unplugging and plugging back in the harddrives whilst the pc was off! The pc was stable enough so i increased the clock speed a bit up to 2.75ghz and low and behold the same problem, same fix worked again however. After repeating this process several times it now all seems to be working properly, running at a nice 2.89ghz needing a slight increase in vcore voltage to make it stable, cooler seems to work well keeping this level of overclocking at around 45 degrees whilst under load.So my question is, why would windows have stopped working when i overclocked only to work again by unplugging and replugging the harddrives? Also the bios tells me i have no ide 80 connector cable installed which it didnt do before, does this mean that i havn't plugged something in correctly? Just thought someone might be intrigued by my odd problem! I suppose it could in fact not be that oddat all and ive jus written a post on 'making myself look like a noob' but you never know!Overclocking seems to prevent Vista from booting?!
Hmm... check the specs of your power supply? Is there enough power being supplied? you have to check the +12v rail. Overclocking seems to prevent Vista from booting?!
Ok, ill check my rails when I eventually have a chance to use my pc, bloody overnight shifts. On Big Brother! How incredibly dull.
[This message was deleted at the request of the original poster]

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