I have a mid-2010 Mac Pro with an ATI 5870 and I believe the fan to be failing. My monitors started randomly going into sleep mode (saying there was no video signal) but the machine stayed on. I noticed that the fan on the card does not appear to be consistently spinning up when I turn on the machine. It is currently spinning (after I gave it a little push) - but it doesn't look very fast and after running iStat, I see that PCIe slot 1 has a temperature of 163 degrees (with the cover of the tower off). Booting into windows the GPU has a temp of 70 degrees. I went to the Apple store (without the machine) to inquire about the procedure and they told me that they'd have to send it out for a week to get it looked at/repaired. It's still under AppleCare and I have the following questions: - I've upgraded the RAM and installed my own SSD boot drive and extra hard drives. Is this going to invalidate my warranty? - I'd like to avoid a week's downtime - are there any other options - like getting them to fix it in store by ordering the appropriate parts? - I'm in the Bay Area - does anyone happen to know where they send the machine to? - Will they give *my* machine back or possibly swap it with a refurb?