Question - One Pcie cable for 2 gpus

[Oarsomeness]

Hey guys,

If we're to get 2 rx480's and crossfire them, is it fine if I power both 6 pin connectors on the 2 cards with one 8+8 pci-e cable or does this require 2 separate cables??

I don't really wanna upgrade my PSU because I bought it 2 weeks ago :c

Cheers

[DXMember]

it depends on the wire gauge and the PSU specification

if it's okay with 300W draw on that cable and the wires are not extremely thin then yes it will be ok

but that is only true if you intend to overclock the cards

if you do not intend to overclock then it will be fine regardless

[roughavoc]

I am confused what you are asking, what PSU do you have

[Dzzope]

12 minutes ago, roughavoc said:

I am confused what you are asking, what PSU do you have

He has a PSU with i pci-e power from the PSU that splits to 2x6+2 pin pci-e connectors.

He wants to know if it's ok to un CF 480's off the 1 power.

 

 

I would guess you will have problems with the amps on the 12V to run the system.

[Oarsomeness]

I've got a Be Quiet System Power 8 500w 80+ unit. I've got 1 pci-e cable that splits off into 8+8 pin connectors.

[Oarsomeness]

10 hours ago, Dzzope said:

He has a PSU with i pci-e power from the PSU that splits to 2x6+2 pin pci-e connectors.

He wants to know if it's ok to un CF 480's off the 1 power.

 

 

I would guess you will have problems with the amps on the 12V to run the system.

 

5

 

How many amps are needed to run 2 GPU's and a CPU?
My CPU is an i5 4460 which is 84w.
It's powered by a 12V CPU cable right?
Using the formula P=VI (Power=Voltage*Current) --> (84/12=7), it would need 7 Amps to run.
If the 2 graphics cards are 150 watts each, then assuming they have 12 volts delivered, P=VI (150/12=12.5) means they will need 12.5 amps each, totalling 25 Amps.

25+7=32 Amps to run the CPU and 2 GPU's
My power supply has 2x 12 V rails with 24A on the first one and 20A on the second, and then it says 38A underneath both.
Are both the CPU and the GPU's placed upon the first rail or are both utilized? 
Pls halp.
Cheers.