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#11
Well done on HPE 380t :) Let us know how the remaining tests go :)
For the ASUS P6T DELUXE V2 one, Replacing AVIRA by MSE is not a part of troubleshooting, but if you feel like, you may do it. Here the important things are the SP1 update, Stop overclocks, checking the heat, and the hardware tests.
About your final question, the HPE 380t one crashed on software level, apparently, but the ASUS P6T DELUXE V2 one crashed on hardware level.
Hope both your computers will run stable after completing the suggested actions. If not, we will check the causes again. At a maximum, it may take a time, but nothing more :)