2 issues - Noise and RAID

It appears that you have a couple failed disks and a fan with some dust bunnies in it. That should be pretty easy to fix.

Back up all your data. If you can't shut down to replace the failed disks and clean it all out, then bring your replacement up that you purchased, and copy the data over to the new one while you clean and rebuild the original one. If you CAN shut down over a weekend or something, you could save a ton of money and hassle.

If you find a noisy fan, clean it or replace it. If you find a noisy disk, replace it. An old trick to pinpoint noise is to put a screwdriver to your ear and hold it against the part until you hear which one is making the noise... a poor man's stethoscope of sorts. Fans make noise when junk gets in them, or they get worn out. Disks make noise when they are failing, too... though usually it sounds more like clicking.

Certainly, you should back up everything, and copy data just like it was. Is the new machine exactly the same - identical drives and everything? If so, you could salvage the working drives from the old machine as backups for the new machine, and after cleaning it completely, setting it up with new drives for a future upgrade or backup. It would be like having a spare motor for a race car, I guess.

I have to say that I'm confused about having bought a whole new machine for what might be dusty fans and a couple failed disks in a RAID. My main RAID has seen a couple disk failures, but I just install replacement drives right away and let it rebuild. I also do a full-on cleaning twice a year, before any dust has time to build up into a wad. If you're not cleaning it regularly, expect more problems.

Thread necromancy, sorry!

Just had an annoying noise in my RAID tower, an old Sans Digital 8-bay mini-SAS TR8X. It was the fan in the power supply rattling.

I'd replaced the main large fan in the rear with a Noctua fan that was MUCH quieter than the lame blue-light fan the unit came with, and had purchased an 80x80x25 Noctua NF-R8 for the power supply, but it was too fat to fit into the power supply enclosure, so I skipped it at the time. I cleaned it annually to try to keep it quiet.

Well, now that little fan was making a noise I just couldn't live with despite cleaning, so I pulled it all apart and modified the box so the Noctua NF-R8 would fit, since it's 10mm thicker. I tried cleaning it thoroughly before putting in the Noctua, but it still rattled, so it was beyond hope. Back to the sound of silent fans (and whirring HDDs) and some peace of mind.

I also just replaced my old Radeon HD 5870 with an MVC-modded R9 280x. Same reason - - the GPU fan was making noise too often, despite cleaning. I didn't feel like completely disassembling the GPU and trying to lube the fan, and I did want a better card anyway, so I felt it was a good time to update to the 280x.

Nice that these things can be done on an old 2009 Mac Pro!
- 4,1 --> 5,1
- Quad core --> 6-core
- Radeon 4870 --> 5870 --> R9 280x
- Apple RAID card --> Areca 1880ix-12
... and so on.

May it keep me from building a new video editing PC for more years to come, and thanks to MVC and Noctua!