yes the event viewer. Expand Windows Logs then select both application and system. On the right hand side you can do a find for those key words. Even if the WEI doesn't show a failure, it still may report something in the EL.
I did as you said, but found no instances of any errors. Did same for each computer. So, to make it easier to locate a possible error, I ran WEI again on both computers. Both runs stopped with the same error. Then I searched for an error immediately afterwards. Nothing. No errors of ANY kind reported in either Application or System portions of Event Viewer.
It's odd that WEI is reporting the same error on both machines. Especially since one machine has a single HDD and the other 2 HDD in RAID 0. Just out of curiosity, I wonder if I swapped the graphics cards back in their respective machines, re-install the drivers, if the problem would go away? Seems like a lot of effort just to get WEI to perform correctly, though...