IE 8 High CPU Usage

Greetings all:

My issue, high CPU usage when using IE8.
What I have already done:

• MalwareBytes (updated and up to date file), full scan, no malware
• AdAware (updated and up to date file), full scan, no issues
• Norton Security Suite (updated and up to date file), full scan, no issues
• IE8, reset software to default settings

Computer:
Sony PCV-RS620G
Pent 4 HT (3.GHz)
2 GB Ram (max)
OS: XP Home, SP3 (all updates)
Anti Virus: Norton Security Suite Ver. 5.1.0.29 (up to date definitions)

High CPU usage started to appear a few weeks ago, I finally found time to try to fix the problem this past weekend, to no avail. Any assistance would be greatly appreciated.

Thanking you in advance;

Crapgame