Motherboard shuts down if not enough power?

A question to some of the tech heads here. Is there a feature/ability in MB’s that will make them not run and actually shut down if the PS isn’t enough for it? I’ve had a recent experience where this happened(A new MB/CPU/memorry and PS(330W) I got for Xmas wouldn’t post, and just shut itself down after a cpl of seconds. When it was hooked to a 400w it posted fine. The 330w PS I got did booted my old MB/CPU fine.

Is this a normal thing if the PS isn’t enough or just something weird.

Sure it’s not shutting down due to heat? I had a power cord that was screwing up with my CPU’s cooling fan, that would cause total shutdown on startup to save the chip.

I had something weird happen where my system all of a sudden rebooted spontaneously on me while I was playing a game and checking my email. Then i remembered that I had set my memory timings to a really agressive setting 2-2-2, when they were 2-3-3 chips. Switched it back and things seem stable again.

I think that’s a normal thing. Have you added up the power requirements for all your components? If it exceeds the power supply’s capacity, I think the power supply should shut itself down.

It’s entirely possible that your old power supply just won’t cut it. And yes, simply cutting off is one possible symptom of an insufficient power supply. You can also maybe get things like blue screens and memory access errors and lockups from power supply problems. Computer errors are like a box of chocolates…

If the only change you made was hooking up a 400W power supply and the machine ran fine, it’s a pretty good bet that’s the problem. The simple solution is to blow $30-50 on a good new power supply (I personally recommend getting more than you think you’ll need, and going for one of those quiet-running models, but I have this thing about my computer’s noise).

One thing people forget also is that it takes more power to turn your computer on than it does to keep it on. When you first boot up, your PS is having to work to spin up drives and so forth. Once they are spinning and things are flowing, however, they require less power.

It’s the same thing as starting and stopping your car at stop lights instead of idling… it takes less fuel (usually) to idle than to shut down, wait, and crank it up again.

I’d recommend you take a look at that Firing Squad guide on picking a power supply and calculating power needs. I just put my new computer together last night, and its power requirements over the previous one are much greater. With all the stuff in this box. I had to look around for a power supply with lots of amperage on the 12v rail, and it was surprisingly hard to find. Generic “400 watt” and even 450 watt power supplies lacked it, putting out between 12 and 15 amps, and I ended up with a 350 watt Enermax that puts out 26 amps on that rail.

Thanks for the link.