Salem/Java based apps crashing the system?

Hiho.. recently I've been getting system crashes (instant reboots after a freeze) while playing or launching Salem. Similar thing happened with new version of minecraft sometime ago only that it was the same freeze followed by bluescreen. (didn't launch it since)
Anyone got any idea on how to fix this?
I saw some old thread on minecraft forums with similar issue that suggested ramsticks could be damaged but they don't seem to be.. (i ran more resource-heavy things than Minecraft or Salem and they ran fine, I had that crash only on Java-based games.
Intel core 2 E8200@2,66 ghz
4 GB ram
Amd radeon hd 6800
Anyone got any idea on how to fix this?

Intel core 2 E8200@2,66 ghz
4 GB ram
Amd radeon hd 6800