Hey guys, just had a few quick questions about the A2 in general, and wanted to get a few opinions. I know this isn't an "A2 general support" thread, but everywhere else I've looked is super sketchy, so I thought that I should try.

So I ordered an A2 110MH/s unit from Zoomhash and I got it in the mail this past Monday. Tested it out with the stock image provided on the SD card to get a general idea of an average hashrate. Had it running for about 3 hours on the "default" 1100MHz frequency, and lo and behold the PSU died while mining. I've contacted Zoomhash about getting a replacement, but I'm starting to get nervous because I haven't gotten a reply in almost 3 days. I'll still hold out hope until the end of the week, but it's looking like I'm going to be replacing the PSU on my own dime, which I'm definitely not thrilled about an extra $220 on top of the $900 already spent...

A few questions I have in regards to using the Version 3.1 or 4.0 firmware with my A2:

- During my bench testing, I received an extremely erratic "average" hashrate while mining Litecoin (slow and steady coin, wasn't on coin-changing multipool). Over the 4 hour period, my 30-minute average ranged from 65MH/s to 90MH/s, spiking back and forth between the two every 10 minutes or so. I'm not at all familiar with how Raspberry Pi's work, but could this problem have been caused by a bad (outdated/defective) image? Or possibly by the near-death power supply? The PSU it was sold with is "supposedly" a 1100W Gold unit, but I wouldn't think that running it on 1100MHz would push the PSU to die like that. I have not opened the case because doing so would "void the warranty" just in case they get back to me with a replacement.

- If I were to replace the power supply myself with a reliable unit, what range of power/efficiency rating should I go with? Based on the answer to that question, what would be the optimum frequency setting I should use with the overclock image? I'd like to get as close as I can to the *advertised* 110MH. Also, assume that the chips and boards that I have are completely untouched and not modded in any way, and I'd prefer to keep it that way since I'm not the best (or luckiest) working with electricity and circuits.

Any help would be greatly appreciated. I might as well learn about the A2 and anticipate what I need to do while I wait to get it fixed. Thanks guys!