Has anyone tried buying some used blade servers for CPU mining ? Some of these are available for 6000 on eBay and I think with 32 CPUs and 400 threads it should be profitable for few months I suppose.
It would probably depend on the memory bandwidth and available memory per thread. Do you have that information?
$6k? I don't think this would be profitable.
Suppose you get 20 sol/s per CPU, that's 640 sols/s for 32 CPUs, which is 9.375 sols/s per dollar. Suppose each CPU is 50W (probably more though), that's 2.5 watts per sol/s.
Now compare that to GPU mining. Suppose you put together a rig for $1600 that has 6 RX480's. Suppose you get 180 sol/s each RX480, that's 1080 sols/s, which is 0.675 sol/s per dollar. This is 13.8 times less expensive than buying a 32 CPU blade server.
I may have a math error or logic error, but seems like GPU mining is still way cheaper.
edit. haha I had typo. Correction : .16 sol per dollar and .675 sol per dollar. ...
Your math is off slightly but only due to the sol per dollar and dollar per sol...: but still very excellent point!
If blade server is 640 sol for $6,000, then...
=$0.106 per sol
If gpu rig is 1080 sol for $1600, then...
=$0.675 per sol
Point being gpu rig is more efficient per dollar than server blade rig.
Dear Op... 400 threads total for 32 CPU doesn't add up. This is 12.5 threads per CPU...? Is isn't linear. Must be typo?
It is HP c7000 with 16 blades, 32 CPUs each one with 6 cores and 12 threads. Total 384 threads. I saw Monero benchmarks showing 15000 Hash for similar systems on Monero.
There was discussion in the past about AWS instances and I am sure all of those instances are running on similar virtualization servers. If you can get one generation older server for 10% the cost, it will beat AWS pricing for sure. I am also thinking that it would also be profitable for the time being.
Of note, I tried Z Cash on Opteron 3280. It has 8 cores and gave about 30 sol/s per core.
Each of these CPUs have 6 cores and with hyper threading 12 threads are possible. What I am not sure is, if each of those threads will generate 20 - 30 sol/s or if it is going to be less.
I ordered a bunch of servers from eBay and should have some results in a week. I will post the results once I get the data.
Not a typo.
If it is Hexacore CPU, you get 384 ( 16* 2 *6 * 2) threads on 16 blades. If it is octa core CPUs, you can get 512 (16 * 2 * 8 * 2 )threads.
I just want to give reference to Monero benchmarks document for better idea on it's performance.
Look at the blade server at the very top on the CPU hash ranking.
6000 / 640 = 9.4 $/sol
1600 / 1080 = 1.5 $/sol
Return to school
Hahaha. I should not type with lack of sleep.
edit. haha I had typo. Correction : 0.16 sol per dollar and 0.675 sol per dollar. ...