Will 3pin CPU fan plug work with 4 pins?

It should work, but you won't have fan control - always on, full speed.

Desktop Boards — 3-wire and 4-wire fan connectors

Thanks, David.

Any suggestions for just the fan, with 4 pin? I'm not coming back til May, he can swap in the fan but doesn't want to paste the heat sink.

I haven't found anything yet for just a CPU fan, if I do I'll post back.

In your OP you stated socket 275.
Is that correct, or is it a typo and it is socket 775?

I've rigged up using a small case fan to replace a GPU fan when i couldn't find a replacement fan...
I removed the GPU HSF shield and fan, then screwed the case fan into the GPU Heat Sink fins.
Probably not something your friend would want to do if he doesn't want to install a new Heat Sink...
Been working for a few years like this with no problems.

Yes socket 775. Sorry, a typo.

Any fan suggestions that would fit and vary speeds as required welcome.

Thanks.

This one is < $15, 92mm, socket 775, 4 pin (pwm).
Newegg.com - Rosewill RCX-Z90-AL 92mm Sleeve CPU Cooler

I don't know if you can just use the fan from this, to replace the fan with the stock Heat Sink.
Maybe you can tell looking at the pics, but it is listed as 92mm.

Will 92mm fan fit if it's replacing a measured 95mm fan circumference?.

That's the big question.
I don't think you can be sure until you have the new fan in hand with the stock Heat Sink.
Will it be easy to attach that 92mm fan...


I'd plan on a worst case plan B, meaning the new Heat Sink will need to be used, requiring pasting.
Do you think the current fan can last till May, if needed?

Not sure as it's flaky, but I imaged C to a new unused Toshiba laptop, plugged his monitor, keyboard and mouse into it and he likes using it as his "desktop" now better than the Acer slimline.

So the urgency has greatly diminished to leaving a link on his desktop, probably this one y'think matching the exact P/N? Acer HI.10800.028 Heatsink and Fan Gateway AX3400G X1420G X1920G

Well, he could use that as his primary for the time being.

If you can get to the bearing on the current fan, you can try adding a drop or two of light machine oil, like sewing machine oil.
This can extend the life for a while, but I don't depend on it for a long term solution.

If he likes the laptop better now, the slimline may become a backup machine...