Have you checked the power brick?
Yep, I hooked it up to my Siglent SDS1000 Oscilloscope (I don't know the exact model because a lot of information was scraped off when I bought it from my college - heh it also annoyingly defaults to Chinese whenever it's turned off, however I have memorized all the menu items/display elements) and I suspect that it was the cause. It ran level for ~10 minutes and then started to produce small oscillations before it spiked high and returned back back to normal. There was no noticeable sound or any other artifact from the power brick when this happened, so I don't know how long this has been going on and if it's been getting progressively worse or is random.
I guess now is a good time to contact Chinese companies (since it's early late morning there at the moment) as I received a very quick reply from their engineer. He suspects that it's a matter of a blown fuse (there is a small white chip on the bottom that makes up the fuse). Since I was also unable to power the board using the alternate molex connection, this seems very likely. I asked for the part number and will replace it after I finish moving (thankfully the oscilloscope was one of the few things I had not packed yet as I'm just moving a few miles across town). On an unrelated note (aside from the fact that it deals with the same board), I still need to figure out why the hashing rate is reaching nowhere near it's peak of 840MH/s using the v42 firmware. I requested -3 quality chips be used, however procurement at reasonable prices, even in bulk, is becoming an issue. I was told ahead of time that -3 and -3N chips were unavailable, so -2 chips would be used. I would think I should still be able to reach ~600MH/s, even with the lower quality.
Also thanks for the reply fpgaminer, I don't think we've ever communicated directly, but I've always have the utmost amount of respect for you (I'm all about open software/open hardware, and as far as Bitcoin you are pretty much the George Washington regarding leading the FPGA open-source movement - heh the analogy might be crummy as I'm falling asleep as I type this, but hopefully gist is clear). Another *unrelated* but do you think bitfury's FPGA source (another person I highly respect if for no other reason than he is well-read; sometimes my brain refuses to input whitepapers, even if I completely understand the concepts being talked about) could be incorporated into the Lancelot design? I have not had a chance to examine the file(s), however I read that it includes source for Spartan-based chips, so it sounds promising. I'm about to faceplant into my keyboard though so I will end this here though. Cross your fingers for me that I don't slip up and trash the Lancelot somehow when replacing the fuse; I always make sure I am well rested or full of caffeine before I let myself near a soldering iron
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