Can computer crashes and reboots be caused by weak power supply?

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?

UPDATE

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.

Tomas Andrle

Posted 2010-04-17T00:22:48.623

Reputation: 2 892

Answers

Yes. Adding more watt load can cause components to run at a lower voltage than they were previously, causing instability and crashing.

Jacob Krall

Posted 2010-04-17T00:22:48.623

Reputation: 207

I have experienced this. I was using old power outlet and experienced strange behaviour from my computer. The problem was solved by replacing the outlet (old wiring remained). – Papuass – 2012-02-01T10:08:09.280

It could be your power supply, or it could be your new video card. Video drivers are notorious for causing crashes in Windows.

Dour High Arch

Posted 2010-04-17T00:22:48.623

Reputation: 1 037

Yeah but Windows Vista and Windows 7 usually handles the crash of the driver pretty well - it only restarts the graphics system. The problem I'm having causes instant reboots or bluescreens. – Tomas Andrle – 2010-04-17T21:14:46.640

+1 for power OR drivers OR windows. If crashes occured during load, then the power supply was the obvious winner here. But when crashing on idle it means something general is failing. I'm not a fan of Windows reinstalls, but what do you think of your Windows performance?

You could also post some info about the video card model and the drivers installed. There could be a known problem with these, that Google can find.

Ivan Petrushev

Posted 2010-04-17T00:22:48.623

Reputation: 1 591

ATI 4670, latest drivers, Windows 7 64bit. As I wrote, before changing the card the computer was 100% stable (running for days, playing games, everything). The crashes do not (necessarily) happen under load. The power supply is 300W. – Tomas Andrle – 2010-04-17T13:11:05.903

You'd better put these details in your question's body. – Ivan Petrushev – 2010-04-17T16:33:34.917