Step 1: Collect Underpants
Step 2: Try the following: A) Can windows Vista start in safe mode? (F8 just just after the POST screen) B) Does windows start if you use "selective startup" and SKIP loading hal.dll ? C) If A & B don't work, try loosening your ram timings (for me, the most common cause of BSoDs) and see if it changes anything.
Step 3: Get back to me with the results of Step 2
Step 4:
Step 5: More Profit! (Who knows how?

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