Windows XP issues with S3 suspend mode


Daemon Poster
I have a Gateway 4015h with a 2.2 GHz AMD Athlon 64 (single-core) processor with 2.5 GB RAM. It supports two low-power states: S1 (POST) and S3 (Suspend to RAM).
I am running two operating systems: Windows XP Professional SP2 and Windows 7 Ultimate x64. When I resume from standby mode S3 in WinXP, the System Idle process is using most (and sometimes all) of my processor, which is very aggravating, because I have to restart the computer to have my processor free again. I have all my drivers installed for WinXP, I even updated my BIOS - to no avail. It does this even on a fresh installation. It works fine on S1 - however, it wakes up by itself frequently and uses more power than S3. But here's the reason this thread is in the Software section: On Windows 7, S3 works fine. No issues. I have both XP and 7 because I am awaiting a processor upgrade and Age of Empires II runs right on XP - but that's another thread. So, please post any suggestions on how to fix this; post links as much as possible, stay to the question, and be nice.

Here's a link to a Wikipedia article if this helps:

To sum up: S3 mode causes System Idle process to use most of my processor in Windows XP. I want to be able to use S3 mode without issue in XP.