If the problem started after reinstalling to a new HD and the rest of the hardware is the same, then you may have a HD or OS problem.
These two possibilities were covered in the first two replies to your post by Keiichi and Pebbly who suggested running System File Checker to check the System Files and Disk Check
to test the HD.
You replied to neither as to whether you ran these tests and what were the results.
In addition, if SFC shows no violations of System Integrity I would consider a Repair Install
, and after chkdsk I would run the HD maker's diag/repair full CD scan: Hard Drive Diagnostics Tools and Utilities (Storage) - TACKtech Corp.
In addition study the logs at Event Viewer>Custom views>Admin to google repeat errors to resolution. Next the Performance log on Advanced Tools accessed by clicking your WEI score link at Computer>Properties. Look for cued issues on Tools page, Generate A System Health Report.
Type "solutions" in Start Search box to see if any have been sent for problems reported or not. Windows 7 is interactive in this way.
After you have exhausted these troubleshootings steps you are left with clean reinstall after wiping the HD of possibly infected or corrupt code. Some tips for getting a perfect install, based on hundreds done here: re-install windows 7