New Power Supply Needed!

[kristalicious]

Hi there. I have a HP Pavillion a1620.uk with a psu of 300watts. I have just purchased an Nvidia GeForce 7600GT to replace my current 7300LE. The only reason is that im a player of The Sims 2 and have 6 expansions plus the original base game. I have been having crashing issues since day one due to my video card being so bad. Hopefully my new card will solve my problem but i need to upgrade my psu to at least 450watts. I really need some help with this...i know how to install a new graphics card and have done it before but i have no idea about psu's and all the numbers that surround them! My system specs are as follows :

Operating System:
Windows XP Professional (5.1, Build 2600) Service Pack 2 (2600.xpsp_sp2_gdr.070227-2254)
Language: English (Regional Setting: English)
System Manufacturer: HP Pavilion 061
System Model: RJ059AA-ABU a1620.uk
BIOS: Phoenix - AwardBIOS v6.00PG
Processor: Intel(R) Pentium(R) D CPU 2.80GHz (2 CPUs)
Memory: 1022MB RAM
Page File: 567MB used, 1890MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 9.0c (4.09.0000.0904)
DX Setup Parameters: Not found
DxDiag Version: 5.03.2600.2180 32bit Unicode

If you need any more information in order to help me please let me know.
Thankyou!!

[Frankie]

Psu are not that hard to fit. Just make sure that as you disconnect the cables that you make a note of where they go, that way when it comes to putting them back, you know where to put them. 450watt psu will be fine. But pay a little more and get a good one.

[kristalicious]

Do i not need a certain one to fit into my tower?

[Frankie]

All the info listed about the computer is listed below. I think it's a micro tower.

http://www.ciao.co.uk/HP_Pavilion_Media_Center_a1620_uk_Pentium_D_820_2_8_GHz__6688422#productdetail