Hi Shrimp, you could try SpeedFan (http://www.almico.com/speedfan.php
To enable CPU logging, Click on Configure, and on the first tab (Temperatures), click on CPU. At the bottom of the window, you will see a "Logged" checkbox. Check this. Then Click on the "Log" Tab, and check "Enabled". Then Click OK, and restart the program for good measure. Then next time your computer crashes, you can check the log for the last temperature it recorded ;P
The logs are store in the same directory that SpeedFan was installed to.
Hope this helps!