Latitude E6400 Overheating

My E6400 freezes several minutes from boot.

I've tried  this and that, even installed new fan, nothing helped. Then I found SpeedFan program, which controls fan. With that program running laptop is not overheating. So  fan is ok.

I do not want to be dependent on speedfan running.

I've tried built in Dell Diagnostic tool, the one you start on boot with F12. It freezes on RTC check.

I'm up to date with BIOS and drivers, as far as I can tell. Regretably When I try to run Analyze tool from dell's support site, it freezes too. I begin to see the pattern here:emotion-39:

Help!?