PSU and Thermal Paste question for new PC

Hey all, I was just wondering if the power supply I have in this build will be enough to run it all smoothly, without pushing it. Also, I've seen a lot of people with thermal paste in their build lists. What exactly is the use of this and will I need something like http://www.pccasegear.com/index.ph [...] ts_id=6738 when I purchase mine? Thanks a lot guys

WWW.PCCASEGEAR.COM

Memory: OCZ DDR3 PC3-10666 Platinum 3x2GB - $165.00
GPU: 2 X Sapphire Radeon HD4890 - $289
PSU: Corsair TX-750 750W Power Supply - $205
CPU Heatsink: Scythe Mugen 2 CPU Cooler - $79
HDD: Western Digital Caviar Black 500GB - $90


Total: $828

MSY

CPU: Intel Core i7 920 1366pin-series - $390
Motherboard: G-B EX58-UD4P - $324
Case: CoolerMaster HAF 932 Case - $209
Optical Drive: SATA SONY - $39

Total: $962

Complete Total: $1790

Hey matt, unless you'll be overclocking, you can make do with a 550W PSU

Thermal paste is usually applied to the CPU, so that it better conducts heat towards the heatsink/fan assembly.

There are many articles on the internet regarding how to apply thermal paste. Just remember, a little goes a long ways as you only want to fill the tiny crevases betwen the HS and PSU.

Corsair 750TX - good unit. Very conservatively designed. Most other vendors would have called it a 1000 watt PSU. One of the other tech sites tested one. It stayed within specs past 900 watts before it electronically shut itself down.