HP Z840 with 3 GPUs, Power Configuration Help

[Brian1965]

Yes, these look like they should be up to the job, based on the 18 AWG wire rating used in these adapter cables.

With regards to the connector shapes, these cables should comply with the PCI power standards, so I don't think that would cause any issues. I assume you already have one of these connectors for your 1070 power?, if not, you will need a third adapter. i.e. all the cards, 1070 + 2x 1080ti, will require 2off PCI supplemental auxiliary power cables.

FYI - If thermals become an issue, the 1080 ti can be modified for water cooling. I purchased a GTX 1080 ti FE and replaced the stock fan cooler with a water block cooler. 

What CPU's do you have installed? You will need 2 CPU's to run 3 GPU's in the Z840. Also, when GPU rendering (CUDA), a higher CPU single threaded performance makes a huge difference to render times.

[4zain4]

Great, Will go a head and order these.

For the 1070, I am using a cable which came with the EVGA SR2 M.B. (my old WS) ... all pins shapes perfectly matches on both ends.

I hope I dont take the water cooling route, Its just I dont like having water in there!  Will keep the WS side cover open and see what happens. Might Install a smoke detector there!

I am running on intel xeon E5-2699 V3. To be honest, With only the 1070 I can see very big improvements with renderings speed... I believe GPU computing is the future! I have always remembered seeing the famous video of Mona Lisa being painted with airguns as a demonstration of how fast GPU compared to CPU and with all software adaptation this becoming real. After seeing UNREAL5 DEOM I was about to cry of all the details they could achieve from the new XBOX 5.   

[Brian1965]

If you are doing a lot of video rendering, then seriously consider changing the CPU to one with a higher single threaded clock speed. (Speaking from personal experience, e.g. Premier Pro, Maya, VRay, Redshift, SolidWorks Visualize, etc.). Your 18-core 2699 v3 CPU has a relative CPU single threaded score of 1768 (PerformanceTest), whereas the 14-core 2697 v3 CPU single threaded score is 1998 (13% faster). Looking on ebay, the 2699 v3 is selling at around £620 and the 2697 v3 is selling at only £350. (These prices are for genuine CPU's - not ES or QS chips). You'll see a boost not only in render times but also in the general responsiveness in other computer applications.

[4zain4]

Thank you for the tip! I have had this WS for 5 years now and it served very well ... I start seeing some limitations. The additional GPUs is something I know I could use for the future rig. I see very strong potentials on the new AMD 3970X (32 cores) & 3990X (64 cores) threadripper, just waiting for prices to go down. Thank you again for the great help