Recently I replaced the videocard in my PC for a newer, faster one. All games work perfectly but I get random system crashes and reboots. This happens even when the system is almost idle (browsing, playing music). It never happened with the old card. All drivers are up-to-date.
Is it possible that the power supply is not powerful enough for the new card?
After replacing the 300W power supply with a 400W one, I also noticed that the old one had a 20-PIN connector for the motherboard. The new one had an additional 4-pin connector which I plugged into the board's 24-pin input. Runs fine now. The new graphics card must have been the culprit; it requires more power and the motherboard power input didn't suffice.