電腦更新成sp2後，上網開網頁的速度變的很慢，常常開不起來，

之後常會出現藍底白字的內容，

A problem has been detected and windows has been shut down to prevent damage
to your computer.

IRQL_NOT_LESS_OR_EQUAL

If this is the first time you've seen this stop error screen,
restart your computer. If this screen appears again, follow
these steps:

Check to make sure any new hardware or software is properly installed.
If this is a new installation, ask your hardware or software manufacturer
for any windows updates you might need.

If problems continue, disable or remove any newly installed hardware
or software. Disable BIOS memory options such as caching or shadowing.
If you need to use Safe mode to remove or disable components, restart
your computer, press F8 to select Advanced Startup Options, and then
select Safe Mode.

Stop:0X0000000A(0xc0000000, 0x00000002, 0x00000000, 0x80506A0F)

Beginning dump of physical memory
physical memory dump complete
Contact your system administrator or technical support group for further
assistance.

我的電腦配備是

品名
AMD Athlon64 X2 4200+
Gigabyte M56S-S3
ELSA 7300GT/256M DDR3 影雷者
A-DATA 1G DDR2-800
Seagate 250G 16MB SATAⅡ
ASUS 1814BLT SATA
海韻 S12Ⅱ-330W
瑞麗 音樂之聲 4聲道PCI音效卡

之前使用一切都正常，是在安裝SP2後才有這樣的問題，
電腦是前幾天新組的，在9/3完成作業系統的安裝，
今天更新後沒多久就出現這樣的問題，
請問是哪裡出問題了？

謝謝