Can we get a breakdown of the mainboard, CPU, drives, etc?

CPU: Q6600 @ 2.40
MOBO: Intel DP965 LT
GPU: 9800GTX
RAM: 4GB DDR2
HDD: Western Digital 250GB

It should hold, but I cant be sure becouse I've never ever heard of Topower PSU-s.

Agreed, a good quality PSU at 650W would be sufficient. However, Topower is a lower-end brand, and I have ZERO experience with them aside from removing blown ones to be replaced. THIS DOESN'T MEAN IT IS BAD, but not a brand I would buy.

Your PSU should have plenty juice for you to upgrade. Amps I think so too as you don't seem to be overclocking.

Putting your computer info into this site http://extreme.outervision.com/psucalculatorlite.jsp can give you an idea of how much watts your need. With the 560 ti I got 367 watts for your system but keep in mind it's only an estimate.

I don't know the brand of your PSU so I won't recommend anything as I have had bad experiences with noname brands.

Hope this helps you :)

Yea, a brand name 650W power supply would do the trick.