Here is something interesting that is not originally intended to be used as a GPU mining rig, but for a powerful compute oriented machine – an 8x GPU AsRock Rack Barebone populated with eight Nvidia GeForce GTX TITAN Z video cards and two 14-core Intel Xeon processors. These powerful rackmount systems are designed for use with Nvidia Tesla cards for high-performance CUDA applications, but you can put in GeForce cards as well such as the TITAN X and have them all running at PCI-E 3.0 x16 speeds (no SLI support is available).
So we took one of these interesting systems and ran a quick test with the latest ccMiner to see what kind of performance we are going to get for crypto currency mining. It was out of curiosity as the system is not intended to be used for GPU GeForce GTX TITAN Z mining – the whole things is just way too expensive to probably ever see ROI let alone make some profit from mining. Interestingly enough the 8x GPU configuration requires the use of Windows Server or compatible Linux distribution, with Windows 7 or 8.x we were having trouble making all 8 GPUs work properly (Error code 43 on the 8th card). Apparently there is a solution to make all 8 cards work fine under these consumer versions of Windows as well, all you need to do is some registry modification and you should be fine.
As you can see from the screenshot the system runs fine with a total hashrate of about 190 MHS mining Quark (98 MHS total on X11 and 25MHS total on Lyra2RE) on all eight GeForce GTX TITAN Z GPUs. This means that a single TITAN X card gets you about 24 MHS for mining Quark-based crypto currencies and ll of the cards manage to provide optimum performance. Notice that the fans are turned all the way to 100% for best performance, because otherwise the cards are easily hitting the thermal limit with their fans running on auto at about 50-60% and as a result they throttle down and you loose performance with the GPU frequency dropping down to 1000 MHz. Again this is not a system designed for crypto currency mining, but for compute applications, we were just curious how well it will perform for crypto mining and it does a great job with some tweaking. Of course since the whole thing is designed to be in a server room the noise level is not relevant, though it is quite high as expected thanks to the 8 GPU fans and the other 8 chassis cooling fans that are 24W each when running at maximum RPM.
Maybe if GPU GeForce GTX TITAN Z mining picks up to a large scale level like it is happening with Bitcoin mining and is profitable enough we might be able to see solutions like these used, but for now these are limited to businesses using them for high-performance CUDA applications. Think along the lines of 3D design, visual effects rendering, medical imaging, energy exploration or scientific simulations etc.