Mining with spare server capacity

[epdp14]

Before everyone gets their panties in a bunch, I own these servers and their main purpose is something other than mining.

I have quite a few servers that have idle processors a good deal of the time. Most have Intel Xeon E5420 processors (4 cores at 2.5g). I have been using ufasoft with very few options (-a 5 is about it). I am not an expert on tuning a miner at all. These servers are running windows server 2008 and that cannot change (as I said, they have a main purpose other than mining). What are your suggestions? I am open to switching mining software or using different options on ufasoft's miner.

[epdp14]

70 Views and no replies? Someone else has to be in my situation.

[SimplePanda]

I really don't think you should bother.

I have dozens and dozens of spare CPU cores available in server farms that I manage (and could utilize no questions asked) and doing the math just didn't add up for me. Even if I throw 64 cores at BTC in their spare time, you're still only really getting 2000khash per core for a total of 128,000khash across the entire 64 core cluster. That's about as much as a single RADEON 5770 worth of computation and you're now dealing with the constant dimeing of your server resources (potentially lowering their lifespan as the fans labour to keep up) plus the energy and cooling (and noise) overhead.

You'd see more return from just buying a cheap-o rig at Best Buy and sticking a couple of 5770 cards in it in SLI.

By all means if a spare server farm is your only cluster go nuts but there isn't much, tuning wise, you can do to make a Xeon keep up with even a trivial onboard GPU.

[epdp14]

So far, I am averaging around 20-30 Mh/s per server. I did not run it with -g no, so t very well could be using the gpu but I dont think so.

[rnd0000]

Just a note. 4-core Phenom II CPU (3400 MHz) can do about 15Mh/s using 4way algorithm.
Unfortunately, I've discovered that too late ;-)
Another unfortunate thing is that CPUs have much less power efficiency than GPUs.
And I've also observed, that if the 'puter does not have powerful enough PSU,
then starting all the cores may cause GPUs to throttle down automatically much more than what CPUs
will give. (same happened when I connected a second hard drive...).