I have a Dell XPS 8500 that's a little less than a year old, and since yesterday I've been getting what sounds like grinding noises from one of the fans near the motherboard for about 30 seconds upon startup. After the 30 seconds it goes away, and the temp looks fine during gaming or normal use. Noise is the same before and after I cleaned the inside of dust.
From reading on the forums this looks like an issue with the bearings of either the CPU or PSU fan wearing out (I'm having a hard time pinpointing the source of the sound even if I put my ear up close to the open case), which is worrisome for such a young computer. Interestingly enough the sounds only happen when the PC is standing upright, not on its side.
I'm going to do a cold startup in a little bit to see if I can identify the source of the noise this time, but I'm posting this now to get some advice on my options. If it's the PSU going bad, great - I wanted to get that thing replaced anyway for a serious GPU upgrade down the line. But if it's a CPU fan problem? I've never researched or messed around with CPU fans and heat sinks before and I could use some advice on that. The CPU is an Ivy Bridge Core i7-3770 (so the socket is presumably LGA 1155). Would I need to just get a new fan or the whole fan and heatsink assembly? How much would I have to spend for a reliable solution? Thanks a lot for the help in advance.
If the noise is only present when the tower is vertical, it's probably the cpu fan.
Easiest way to "hear" each fan is to use an empty paper towel tube next to your ear with the other end near fan of your choice.
You can replace the fan alone (think it's a 92mm), but if it were me, I'd pop for $25 and get an aftermarket cooler like the Hyper 212 EVO or Xigmatek GAIA and replace the entire cooler. It's not a difficult job, just be gentle when removing the stock heat sink. A gentle twisting motion (lock lever in down position) should break the sink loose for removal. If that proves difficult, run the pc for a bit to heat up the thermal compound and then shut down and try immediately while the TIM is warm.
Removing the old TIM from the cpu is done with alcohol and a lint free cloth, and there are many tutorials on applying new TIM (it will come with the cooler) and reseating the new cooler.
Nice thing about aftermarket coolers is the fans are clip on, standard sizes and easily replaceable.