Yo-

As jwill427 so aptly said - watch out for propriety power supply units - especially in brand names like a Sony Vaio

My old Vaio had a power supply that was only 3 inches long - the shortest aftermarket psu I could find was like 5 1/4 inches long - which definitely not have worked - and allowed me to keep my burners-

Conversely - I replaced my new HP a1410n 300 watt with a 500 watt (added a eVga 6800GS video card and am running a BenQ and LG burners-all of which require a large amount of wattage) and the original and replacement length were both 5 1/4 inches-

It really pays off to check and measure your power supplies before you buy a replacement.

Mike