How big of a power supply do you have? Four hard drives + 3 optical drives... then a GeForce 4 on top of that... I'm guessing if you have anything less than a 400W power supply, it's not going to handle it well.
Btw... why do you need 4 HDs and 3 optical drives anyway? I can understand you may be running a RAID array with the hard drives, but 3 opticals? That one has me puzzled. At the most... all you should need are 2 optical drives. (I have a DVD-CD/RW combo + a DVD RW).
<font color=red> If you design software that is fool-proof, only a fool will want to use it. </font color=red>