Is It Safe to Power on a Computer with No CPU

[Arsynic]

I want to test some fans and a waterblock and radiator (for leaks). Can I power up a motherboard with just the memory in it and let it run without frying anything?

 

[PottedMeat]

it won't hurt, but i think you need a working cpu to get the motherboard to power the fan headers.

 

[VirtualLarry]

No, it can damage certain motherboards.

 

[Binky]

I think you can trick the power supply into turning on without plugging it into the MB. Look into that instead. I remember shorting certain pins with a paperclip.

 

[Mark R]

Look at this way. If the worst does happen, it's unlikely to damage the CPU.

 

[PottedMeat]

No, it can damage certain motherboards.

really? i figured no cpu ~= bad cpu so the motherboard halts boot up.

 

[muskie32]

How long do you have to wait for the cpu to arrive?

 

[mfenn]

Wouldn't you want to test your watercooling loop without any sensitive components installed?

 

[Binky]

Try something like this:

http://www.gideontech.com/content/articles/196/1

If you break it, its not my fault.

 

[SKORPI0]

Try something like this:

http://www.gideontech.com/content/articles/196/1

If you break it, its not my fault.

If your PSU has an off/on switch, use a paperclip.

 

[Arsynic]

How long do you have to wait for the cpu to arrive?

Monday.

 

[muskie32]

that does not seem like a bad wait...
Is it worth the risk...?
It could extend the wait a little more...

 

[Arsynic]

I wanted to test the fans and the loop outside of the case before I plugged everything in.

 

[Scoobuh]

Look at this way. If the worst does happen, it's unlikely to damage the CPU.

lol. Very true!

 

[pukemon]

Dunno how many old timers there are out there, but if you happen to have an old AT power supply, you can power on and test anything with a standard 12V Molex connector (or the 5V floppy connector) without plugging in your motherboard.

For those that remember AT mobo power were two connectors that fit but if you plugged in backwards could fry the board.

 

[Bl0cks]

Personally, to test a loop and pump, I would use the paperclip method.

 

[Ketchup]

No, it can damage certain motherboards.

I see no way this would damage the motherboard. As others have mentioned, though, the paperclip method would ensure none of your hardware risks getting fried.