Jet plane Puter

Hey all
Got a minor issue with my system ...
I have a P4 2.8ghz 512RAM running XP all in a Raidmax case, very sharp - the mirage 278.
After my computer is on more than 30-60 minutes it sounds like a mini jet plane. I installed an Antec power supply - 430 Watt ATX12V - which is supposed to be very low noise.
That's really the only issue with my system. I've noticed when I removed the dvd (internal) it made no fan noise at all, just with the cdrw connected.
Any advice would be very much appreciated - it's getting me crazy!
Thanks again,
~mlou

this may sound silly but,,,is thare a cd in your cdrw?,i have noticed my burner spins up for no reason. i take any cd's out and thares no spin-up.

nope no cd, just fan noise. I suppose if I wanted a silent computer I would need to do more than install a new power supply as I've done. I've searched the forum and came across some of the extensive modifications required for a silent system. I guess I was hoping there was a simpler solution someone would recommend.
thanks for replying!