Computer ?
 

I have an older Antec case that has a 120mm rear fan. The fan is almost done. It plugs directly into the PS. I put a new fan in that plugs into the MB. It wouldn't boot up. Put the old one back in and it put up a repair message and wouldn't boot up. I finally hit the restart button since it wasn't doing anything and it booted up. Any idea why it wouldn't take the new fan?

Does the new fan ohm out at a reasonable reading? A dead short could do this. Should be a few ohms (not sure exact but not zero) but if it looks ok in that regard then no idea. Shouldn’t even matter polarity wise.

Say a fan uses 5 watts. The voltage is 5 volts. P=V*v/R. R=V*V/P=5 ohms. Should be in that range.

Don't know but the fan worked when I turned it on.

It's been a while since I messed with PC components, but some fans that plug into MBs have connections for sensing, speed control, or whatever. Maybe the new fan isn't compatible, so the MB thinks there's no fan running & won't boot? You might want to run down the connector pin connections on the fan cable & MB & make sure they look correct. :island14:

I can think of no reason for a case fan to prevent a PC from booting up. My bet is your old POS computer is failing and it just happened to spaz out on you when you powered it up after swapping in the new fan.

More data is called for. Does the new fan work if you leave the old one plugged into the PS? Does the new fan work in a different PC?Does the PC boot if you unplug all the fans? :waiting:

I never heard of a fan being plugged directly into the PS. I've used several Antec cases, and the rear fan will usually either plug into the motherboard connector, or plug into one of the PS power leads. Maybe a pic may help. The only thing that comes to mind if the positive and negative leads of the fan are reversed.

I'm pretty sure he means that it has a molex plug that plugs into one of the PS cables, and then a female fan plug on the other end of the molex plug for the fan to plug in.

Almost every case fan comes with a small adapter cable to convert the motherboard fan connector plug into a standard Molex plug for people who don't have a fan jack available on the motherboard.

Yes, this is my old Windows XP case I put new parts in.

New fan worked when plugged into the MB but the computer wouldn't load. It would get to the loading screen and just have the little thing spinning that shows up when it's loading but not doing anything. put the old fan back in and it did the same thing after putting up a message about launching repair something or other. The message would disappear but the thing stayed spinning. I eventually hit the restart button and hit to restore to a previous point. It chose what point and ended up working. Old fan has been in since then and the computer loads fine again. Fan is still going out though. It struggles to get started spinning but after it does, it seems to keep spinning fine.

I have this case on the way now. https://www.newegg.com/black-antec-p...82E16811129209

You realize that new fans are like $4 dollars on Amazon, right? :lol:

Yes. I paid $5 for this new one locally. :lol:

I'll bet you a bottle of scotch that if you put the new fan back in your PC will continue to work. ;)

What would make it work now when it didn't before?

My theory is your booting problem has nothing to do with the fan, and that it was just a coincidence. Prove me wrong. :waiting:

I will try it later when I'm not using it. :seasix: