More fan noise after dusting

[space6011]

I was cleaning years of dust out a optiplex 780 (one of those very thin mini towers) using compressed air. I couldn't finish the job because I ran out of air. After plugging the computer back in I notice it makes[strike] considerably[/strike] more noise than the same computer that I have yet clean. not much, but it's audible.

Obviously I must have blown some dust where it doesn't belong, I'm wondering if I should just leave the computer off until I get some more air or not worry about it for now.

Edited for clarification

 

[kapitalistas]

http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=-1&IsNodeId=1&Description=cans%20with%20compressed%20air&page=1&bop=And&Order=PRICE&PageSize=90 using this product may be good again.you wanna clear all dust.

 

[mgolus]

The bearings in your fans may be bad which can lead to a very noisy system. Getting every spec of dust off the fans isn't going to help if your fans are shot. You can probably get a replacement for whatever fan is causing the noise on a website like NewEgg, unless the fan is in your power supply. Even in the power supply it may be possible to replace it, as long as you don't mind doing a bit of soldering. Otherwise you may need to replace the power supply.

Also, if you sprayed the compressed air on the fan causing it to ramp up to higher RPMs than it's usual operating speed, you can burn out the bearings. In general it's probably a good idea to hold the fan still while you blow the dust off of it.

 

[space6011]

The bearings in your fans may be bad which can lead to a very noisy system. Getting every spec of dust off the fans isn't going to help if your fans are shot. You can probably get a replacement for whatever fan is causing the noise on a website like NewEgg, unless the fan is in your power supply. Even in the power supply it may be possible to replace it, as long as you don't mind doing a bit of soldering. Otherwise you may need to replace the power supply.

Also, if you sprayed the compressed air on the fan causing it to ramp up to higher RPMs than it's usual operating speed, you can burn out the bearings. In general it's probably a good idea to hold the fan still while you blow the dust off of it.

Well I didn't spin the fan up (learned before working on this system, but wish I had known sooner). The sound seems to be coming from the CPU heatsink fan. It's not a normal fan, it's a fan within a heatsink.

The computer is relatively old, small, and (was) filled with dust, so messing with it probably didn't help that fan very much.

I'll just have to keep an eye on the fan to make sure it doesn't die and damage the CPU. Sooner or later (probably sooner) I'll order a used heatsink to replace it.