Power draw from riser with 1080ti (2x 8pin)

[johny78]

Hello.
Got question.
If i have 1080ti which is connected with 2x 8pin is it going to draw any power from pci (riser) ?
At 100%tdp card draw 250W, 2x8pin should provide up to 300W. So should i leave at least 50W per riser?

My rig is connected like this
PSU 750W powering:
-mobo (cpu, ssd, 6risers)     
-2x 1080ti                       

PSU 1200W
-4x 1080ti

Everything is good, Rig is running undervolted anyways
I have been trying different connections, gpu+riser per psu also, all have been working fine for me
But if i want to run mobo+risers from first psu, and gpu's from second psu, should i always leave that 50-75w free per riser?

[tadeus1]

Yes, it will. 
but how much each GPU uses from the PCI-E cable vs the slot is up to the manufacturer specs. 

If it was me, I would always leave 75W for the raiser, although the Sata connectors' limits are usually around the 55W

[leonix007]

Hello.
Got question.
If i have 1080ti which is connected with 2x 8pin is it going to draw any power from pci (riser) ?
At 100%tdp card draw 250W, 2x8pin should provide up to 300W. So should i leave at least 50W per riser?

My rig is connected like this
PSU 750W powering:
-mobo (cpu, ssd, 6risers)    
-2x 1080ti                      

PSU 1200W
-4x 1080ti

Everything is good, Rig is running undervolted anyways
I have been trying different connections, gpu+riser per psu also, all have been working fine for me
But if i want to run mobo+risers from first psu, and gpu's from second psu, should i always leave that 50-75w free per riser?

Better to properly distribute all GPU and Riser power based on your PSU ratings, 75w for riser is fine by looking at your build seems your PSU could really handle your setup, there is only one thing I've noticed as you put all your 6 powered risers in 750w psu and might stressed out, its just a precaution

[killerelite]

Your build seems fine no need to worry that much if your 750 watt psu is from a good manufacturer and of good series
if its some from cheap series then that might fail over some time
anyways remember to not use more the two risers on a single sata cable /module
Have been using 3 1080 tis and a 1070 on a coolermaster v1000 for 5 months + and its still going strong