Replaced Mobo, now fan very loud

[Thinka]

Hi all, got one that seems strange (well to me anyway).

I replaced the motherboard in an HP DC5100 tower yesterday. Got the new Mobo from HP so no problem there I shouldn't think. I installed it and when I put the PC on, I got a screen telling me about a drive - diskette error. It could see the RAM and the HD though. The error seemed to be referring to the computer not having a floppy disk drive, (which it doesn't), so I pressed F1 to save changes, and it booted. All this time the fan seemed to be spinning quite fast and so very loud. the computer booted up to the login page. At this point I decided to shut down, and then power up the computer again hoping that this time the fan wouldn't be so loud. I did, but the noise didn't stop. I then tried to see if I could load up Windows (XP) alright. This it did, all the programs and documents are on there, but so was the noise, and it was constant. In the end I decided to shut it down. I haven't turned it on since for fear that it'd be making a bad situation worse.

To describe the noise, I would say it's similar to the noise made by a switch, or more accurately, like the noise a Proliant ML150 server makes in the first 3 - 5 seconds after you push the "ON" button.

Is this a case of overheating. The only thing I would be iffy about in my installation is greasing the processor - I did, using all the grease that HP supplied, but I personally didn't think it was enough. Could it be any other thing? All help appreciated please, cheers.

[acejames1]

did you clean the fan when you changed the mobo. also make sure you aint got any excess cover fillers not there in the back of your tower. to run the computer the way it was meant to be you should have anything that should be there on or at least no excess air circulating thru the computer.

[Thinka]

Yea I did clean the fan, well the fan at the back of the tower, not the one on the heatsink. Will take it out and clean it again tho. Also I'm not familiar with "cover fillers"? Could you expand please? And I plugged back everything that was plugged on the old mobo too.

[acejames1]

pci cover slots they should be covered in the back of you pc

[Thinka]

Hey, sorry for somewhat late reply, yes all the PCI slots are covered. A friend suggested for me to actually disconnect the chassis fan (the troublesome one), which I did. However this only brought up an "error" page when I started the computer, sayin it couldn't detect the fan. And also, the heatsink fan just ended up whirring away anyway and making similar noise.

I've been thinkin, could grease (or lack of it) in between the processor and underside of heatsink be the cause?

[acejames1]

naw that wouldnt be a problem. the last thing i can think of would be go buy a new fan will probably clear up all the problems my thought is is that the fan is dying which slowly decreases its speed making it work harder to keep the cpu cooled down like it is suppose to

[The New Normal]

Try putting a few grommets between your fan and the chassis in case it's vibrations causing your noise (if that's it you should be able to feel the vibration by putting your hand near it... carefully). I cut some small squares out of a rubber mat, and sandwiched them in where the screws go, between fan and case. I also did this with my Hard Drives, quietened things a little bit.

It's a remote possibility that your new motherboard is pumping a little bit more Voltage into it, making it spin faster.

Acejames' suggestion of a new fan is probably your best bet though, they're fairly cheap.

With CPU fan, too much goop could make the CPU hot and the fan spin faster to compensate, but this wouldn't happen immediately you turn on the puta. You want a really thin layer so the 2 bits of metal are as close together as possible.

[Thinka]

Cheers guys, some great points coming across. Will try ur suggestions and post back results