Ok, got a 5th card. Since I am maxed out at 4 cards with a 1200 watt power supply I had to get another power supply. I plan on eventually having two 4 card rigs but until I get more GPUs I will use the second rigs PS and GPUs in the first one.
Will also be running up against the max of 16 amps on the 20 amp circuit I have. May or may not be able to run 6 GPUs until I can get a higher amp circuit. At that point I will be switching to 208 volt from 120 I'm using now.
The second power supply is also a Corsair AX1200i. This picture shows the two CorsairLink interface units. Since CorsairLink only supports reporting on one PS at a time I have to disable one and then enable the other (in device manager) to see it's individual power usage. A nice surprise was that even though some of the GPUs are being used on the second power supply, CorsairLink still see's them for monitoring.
Here is a pic of the case with the GPUs now facing the front of the rack (cold air isle). You can also see the temporary orientation of the two power supplies. You might notice that I am only using powered risers on the first 4 GPUs. Think I'm okay not powering the 5th one. If I had 6 or 7 GPUs then I would break out another molex cable to the power supply. I may still do that just for the 5th GPU.
Close up of the connections. 1st power supply has 3 GPUs + 8pin MB + SATA power. 2nd power supply has 2 GPUs + 4 connector molex cable. I can now see that if this was going to be a permanent setup the case should of been made longer so there could be more space between the GPUs and power supplies. The additional space would facilitate easier cable management and allow some distance between the GPUs and the PS since these particular GPUs expel the majority of hot air towards the power supplies. Even with one PS a longer case to distance the PS from the GPUs would (I think) have been beneficial.
