I've been missing out on some PPD. Prior to yesterday, I thought my hard limit on GPUs were 2 per motherboard, but I was wrong. I dug through the specs on the 3 motherboards I have and realized one of them supports 8x8x4, so I upgraded my PSU, purchased a riser, and plopped another card in for even more PPD! I was thinking I was going to have to go through another build to eek out more PPD. 4x doesn't appear to limit PPD at all. 
 

 
Don't judge the cable management. I'm still trying to figure out heating issues.

 
I'm going to look at adding more cards via other PCI ports and see what output is like from an 1070 over 1x. 
 
So, if you're looking for some more PPD, don't discount unused PCIe slots and buy a riser. You'll be able to add some PPD that you otherwise wouldn't have due to space limitations.

if it is pcie 3.0 then 4x will be at nearly 100% buss usage. can you open a monitoring program that shows buss usage and share a pic of that? i am quite interested to see the usage of those 1080ti's as well as the pcie x4 slot gpu, which i would assume is the 1070.

Chris21010
if it is pcie 3.0 then 4x will be at nearly 100% buss usage. can you open a monitoring program that shows buss usage and share a pic of that? i am quite interested to see the usage of those 1080ti's as well as the pcie x4 slot gpu, which i would assume is the 1070.

It's actually a 1080 Ti on the x4 slot. The MSI 1080 Ti runs really hot, so it's the card I wanted outside the box (thus the coolest).
 

Chris21010
if it is pcie 3.0 then 4x will be at nearly 100% buss usage. can you open a monitoring program that shows buss usage and share a pic of that? i am quite interested to see the usage of those 1080ti's as well as the pcie x4 slot gpu, which i would assume is the 1070.

 
I can't upload to Imgur, but it's actually only running at ~60% on x4.

Chris21010
 
really?!  o_0 my 1070's on pcie x8 are using 45-50%... i would have assumed that halving the lanes would double the buss usage if its pushing the same volume of data. now i am curious as to the two 1080ti's actual PPD over a few days. will one be hindered and by how much?

670 FTW running at 16% over x1.
 

Hughesy26
I would be wary of what the bus usage % says. I know my 1080 showed about 50% usage when I moved to it a gen 3 x4 slot but the PPD definitely did drop significantly - from ~850k ppd to 550-700k.
 
It took me a while to figure out what was going on as FAH did it's helpful trick of misslabeling all the GPUs in the system, so I thought it was my 980ti that was getting 550k-700k (which would have been OK).
 

Interesting. I had one FAH client doing the same. That being said, my 1080 Ti on x4 is outputting the same PPD as my 1080 Ti on x8.

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That makes sense... [sm=001_tt2.gif
 
You mean x8?

Right.