squeeling machine

working on a dimension 3100. client first told me that the fan was making a loud noise. at first i just told her to clean the fan with canned air and make sure the blades were clean also. that didnt work so when i went over and heard the noise it was a noise i have never heard before. definitely coming from the case fan but yet the fan was spinning just fine. replaced the case fan and housing unit with a new one fortunately not expensive. in this particular machine you have to remove the heat sink from system to get at the case fan. so when i cleaned off the thermal compound and put new then put machine back together all was okay for about 3 hours then my god the squeeling came back. loudest squeeling ive ever heard and again the fan is spinning. if i keep the heat sink off and just turn machine on the fan seems to go much faster than it should almost like a jet engine as far as how fast its going. when i put the housing bracket that contains the heat sink back on and fire it up the noise is back almost immediately.

any thoughts....greg

 

Are you sure the fan blades aren't striking anything?

 

Chiles4

i believe its a 120mm fan but the fan is built into a housing and its new even has a new car smell so i know its a new one and not refurb'd. i checked and theres at least 1/8 inch between blades and housing.

i have had the machine up and running now since i posted the question and so far the noise is not happening but this has been the symptons before. works for awhile then boom and if you start the machine right away noise is right away but if you let machine rest then start it up noise is not there. ive worked on machine for a lot of years and i have never heard this squeeling very high pitched noise before ever. and yet when the noise happens the fan spins just fine and its not like a noise would be if the blades were hitting the housing that would be more of a thud type noise this is more like a banchee in heat.

only thing i can think of is the housing for the heat sink but cant really remove that for any length of time for fear no air flow in the processor will fry it and the board. the old case fan was in a nasty condition even after i cleaned it so this new one should have done the trick. am totally confused at this one.

 

I'm kind of out of my league here but thought I'd mention this and one of the hardware guys can comment on it. I've never experienced it myself but it seems to me I've read that a capacitor on the motherboard can make a squeeling noise when they are going bad.

One of you hardware guys know anything about this? It came to mind so I thought I'd mention it.

 

zander

actually ive heard some thing similar but thought it was more of a hissing sound and that it would be constant. i hope like you say one of the hdw experts might comment on this. darn machine is still running just fine now for about 3 hours. based on last night when i put the new fan and housing in it was 3 hours or so when it started. so we'll see. thanks...greg

 

more info - noise happened again it seems like a 4 hour cycle except if when the noise happens and you shut the machine down and bring it right back up the noise is immediate.

i took a chance and pulled out the heat sink and disconnected the case fan from the system board and guess what the noise came right back. so its not the case fan so what the heck could it be. right now i have the sata disconnted and no noise. i have a green steady power light but an amber steady board light. always thought that light should also be green not amber.

right now i am leaning toward the hard drive. i have heard a lot of noises coming from hard drives but if this is the drive its a first for me. has anyone heard this type of noise come from a h.d. ??? wish there was a better way to describe the noise but its a high pitched squeeling is all i think of to describe it.

 

Go into your BIOS and disable (if available) any settings that would shut down the machine on CPU fan failure. Note: based on your description this sounds like one of those engineering marvels that uses a ducted plastic port over the CPU heatsink and exhausts out the back of the case as opposed to a dedicated fan mounted directly on the heatsink itself. Regardless of the type, disable any BIOS setting as noted above.

Then wait until you get that noise again and disconnect power to the fan while the machine is running. Then shutdown the machine after 10-15 seconds of listening and observation. Now - did the noise go away when you killed power to the fan? Make sure you reconnect the fan before starting back up or trying to run for more than a few seconds. You can also (if you can reach it with or without the ducted port in place) press on the center of the fan over the bearings while its running and momemtarily stop the fan to determine if the noise is coming from the fan.

I mention the above because you were initially convinced it was a fan (enough so that you replaced it). If that proves fruitless, look at the chipset fan and stop this momentarily by hand to test it as well.

If neither of those are the culprit - check any and all other fans and then move to that hard drive you mentioned. Put you hand on the top of it and assess the vibration. Just as you can hear a squeal, you should be able to feel it. Don't push or squeeze, just rest your hand gently on the top side of the drive. If its mounted in a cage, you may have to remove it to perform this task while the machine is running and acting noisy.

If you do suspect the HDD - clone it immediately and then test it further with the confidence that you have at least, "saved the bacon ".

 

Rockster2U

no its not one of dells wonderful green shoot that swings into place and blow onto the cpu. close though the new dells incl this one have a 120mm fan mounted firmly into a housing bracket. it then is attached to brackets in the case frame itself. next another housing unit that swings into place on brackets mounted on the case this housing unit also contains the heatsink which swings down to cover the processor. nifty little mechanism. only fan in the whole machine. this fan blows directly across into the baffles of the heat sink.

i no longer believe its the fan. last time it made the noise i powered down and immediately disconnected the fan from the board and removed the heat sink housing turned machine on and the noise was immediate even though fan not running nor is the heat sink attached to the cpu. it was quick so turned off right away as not to damage the processor. so even with the fan disconnected it still made the noise.

there is no chipset fan only the 120mm case fan. WOW just like that the noise started so i unplug the connector to the case fan noise still there. tried to pull h.d. out of bracket but to tight shut system down pulled drive restated noise gone. **** what the heck is it. h.d. feels like its spinning okay. i do however feel thumps when i have my hands on both sides of the drive but yet xp comes up just fine no indication of h.d. problem. will have to wait for noise to come back to feel it again.

this is really strange. only thing in that area where the noise seems to be coming besides the fan is the h.d. will need a good stiff drink after this one.