z820 z840 using Nvidia Tesla p40 : questions on Cooling and Power

[Scoobis]

since the nvidia tesla p40 is passivly cooled, is there enough airflow to cool the p40 card(s) in a z820 / z840 without adding some kind of auxilary cooling?  i know the cards are aorund 250W each.

also if you do run them without additional cooling ... have you run into throttling issues running them that way?

my second question is about power  i am aware of the diffrence in the gpu cable and the adapter needed for the p40, and the combinder calbe needed to run it... however....  if i run 2 P40  cards then there are only 3 cables capable of 18a max each for gpus. combining two for the first card is petty stright forward but to run 2 cards the 3rd cable alone cant provide enougn power for th second gpu.   I was thinking of combining all 3 then break them out to the two cards? in thory that be enough power.  for both as need of aobut 250 wtcs each or 500w total, and the supply would be capable of 648W arss the 3 gpu cables and still be insidde its limits.  has anyone done this?

making a custom cable is soming i can do so that is no problem.

[DGroves]

no, the z820/840 workstations can not properly cool the p40 passively you would have to modify/hack a cooling solution

the easiest method is to use a reference nvidia 1080 card that used a BLOWER style cooling solution that some oem's such as dell  sold in their systems

also this card will absolutely require the upgraded 1200 watt power supply and the main (video display) card will have to be under 100 watts in order to prevent the power supplies GPU Rail capacity from being exceeded

don't even think about dual p40's as it's not going to work unless you can find a external 12v GPU power supply these were made some time ago for installation in a 5.25 bay failing that again you would need to hack a 12v DC 300 watt supply and then provide a solution to power it on/off  in sync with the HP power supply

please read some of my previous posts on the z series "multi rail" power supply vs todays pc single rail power supplies