Why is my PC running slow?

Ok my PC is 1 year old and it is running very very slow only the Internet Explorer and Google Chrome everything else works fine i have Rogers extreme internet so it not my internet

You can just google HPE 500F

or here are the specs
AMD Phenom x6 2.7ghz
8gb RAM
1500gb HDD
Radeon 6450

Again only the internet explorer and google chrome take forever to open i have McAfee 2012 Total protection so no viruses, i even download advanced system care to speed it up but nothing changed

My laptop is about 6 months old it runs perfect extremely fast

Specs:
Pentium B950 2.1ghz
4gb RAM
500gb HDD
Intel HD Graphics

why then my laptop is nothing compared to my pc but internet explorer and google chrome load faster on it

I defrag my HDD every month by using Smart defrag
Please Help it has been runing like this for 3 months now
10 minutes ago
– 4 days left to answer.

Additional Details

Please dont give me stupid answers like Mike did
If there is any software ypu recomend please do so (I wont hesitate buying it no matter how much it costs just make this computer faster)
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