Power supply.  You need to buy a real PSU.  Viper sounds like some crap Chinese junk that's probably outputting more like 300W than the rated 750W.

Good, we didn't ask for you help in the first place. 

Clueless.    

I've got a Windows machine mining, and it's somewhere near 100 days since it was rebooted.  It's an ancient old Dell machine, so it's not even anything fancy - it had 5 years of 24/7 use as a desktop, I stuck a couple of GPUs in it, and dumped it in the corner of the server room, and now it's just sitting there mining happily.  Heck, it's still running cgminer 2.something

Well the Cube doesn't really need anything to run.  But, you can run BFGMiner on the Mac using nwooll's Homebrew scripts.

I think if you're going to invest $14k, you should do a bit more research, rather than just asking a question here.  There's so much information on this forum (hint, start in the Hardware forums). 

800+ is impossible.  My elcheapo MSI 280X only gets 688kH, because it's crappy core only does 980MHz stable.  720kH is the normal top-end speed of these cards, 800kH is a drug-induced hallucination.

You need to fan cool the miners.

I highly doubt you have a HD5970 with 256MB of RAM.  The standard for a 5970 is 2GB, 1GB per chip. 

It should mine DOGE fine, probably about 500kH.

Fair enough, I understand the want to make your own mining program. 

To me, a non-programmer, it would make sense to merge your code in to something that's already a solid, stable, well supported program that already has all that groundwork done.  To me, you're reinventing the wheel.

Which version of drivers are you trying?  Would have been useful information in the first post.

Would the author consider talking to Luke-Jr about adding CUDA support to bfgminer?

See: https://bitcointalk.org/index.php?topic=168174.msg5333306#msg5333306

You're in cloud kookoo land if you thing $300 is a high performance PC.  Add a zero to the end of that and you're getting there.

Though, all that said, if you could spend $500 you could get a decent enough machine - $200 for a low-end PC that has two PCI-E slots.  Add a pair of nVidia 750Ti cards which give you about 500kH with less than 120W power use.  Mine altcoins, with that and you'll get about 0.005BTC a day from somewhere like Wafflepool or Scryptguild.

Obviously you need to put the board in the dishwasher on it's own, not with your lasagna dish and cereal bowls.  You don't want a lump of beef or a Rice Krispie stuck in your PCI-E slots.

You shouldn't need to rinse your risers if you don't get them soapy.

So, nVidia's new Maxwell cards (the GTX 750Ti is the first one available) do 245kH at less than 60W power consumption.  Is there any chance of bfgminer incorporating CUDA mining?  CUDAMiner seems a bit of a bodge of pooler's CPUMiner.  

To quote Tom's:
Today, four GM107-based cards in a mining rig should be able to outperform a Radeon R9 290X for less money, using less power.

Maybe everyone could send the forum operator some BTC to get some better software?  I recon 6000BTC would do it.   

You're down to your last BTC4999, can't afford to pay for a real host, eh?   

You need to figure out what it is you bought.  You say Bitmine, then you say Bitemine, and I'm not sure what KNC has got anything to do with it.

Yeah, you're using outdated, old, crap software. 

Try something made recently like sgminer that works with recent drivers and hardware.

I've got one.  It's OK, but it's not the most reliable thing.  

They pretend to be an Avalon, which is totally bizarre.  cgminer does support them.  

Mine does freak out quite a bit, it either just stops hashing, ZOMBIES, goes totally dead, or hangs up then turns its fan off and heats up to about 120C.  I get about 51GH out of mine, at 275MHz/1.1V.  It's got it's own PSU, so it's not a power issue as far as I can tell.