How to properly power GPU

[Simon771]

So I recently bought RM 650x corsair PSU, and noticed something about power cables for GPU.

 

 

So I got 2 of those cables, and wasn't sure how to use it. My R9 390 nitro does use a lot of power, so I didn't want to use only 1 cable.

So I used both of those cables, and connected only 1x8pin from each of them.

 

Do you think if I only use 1 of that cable, it would still work? I don't want to starve my GPU from power  

Any idea how much power can 1 of those cables deliver?

[Bananasplit_00]

its fine with one cable probably, check in GPU-Z for the preformance limiter and if its power then maby 2 cables is the way to go but more then likely not, just go with one and have a nicer time with cable management  

[Mr.Meerkat]

Each 8 pin is capable of delivering 150 watts of power (a 6 pin can deliver 75Watts of power), there's no real reason for you not to use the single cable with the 2 x PCIe connectors as they are designed to be able to output 300W (in total) from the 2 connectors  and you will not starve the GPU as you're allowing it to consume up to 375 watts of power (75w is from the PCIe interface) so yeah, one cable is fine as they are designed like that.

[Simon771]

5 minutes ago, Bananasplit_00 said:

its fine with one cable probably, check in GPU-Z for the preformance limiter and if its power then maby 2 cables is the way to go but more then likely not, just go with one and have a nicer time with cable management  

 

3 minutes ago, Mr.Meerkat said:

Each 8 pin is capable of delivering 150 watts of power (a 6 pin can deliver 75Watts of power), there's no real reason for you not to use the single cable with the 2 x PCIe connectors as they are designed to be able to output 300W (in total) from the 2 connectors  and you will not starve the GPU as you're allowing it to consume up to 375 watts of power (75w is from the PCIe interface) so yeah, one cable is fine as they are designed like that.

 

So I will remove one cable to get more space in my case  

Right now cables are kinda tight because I'm also using cable extantions, just because I wanna have white cables  

 

I heard about that 150W somewhere before, but I taught 150W is from the PSU end of the cable, so 75W for each at GPU end. Seems like I was wrong.

 

Thanks for info guys.

[Enderman]

one cable is enough

 

the only reason you might want to use two cables is if you have a crappy power supply that only only deliver a small amount of watts on a single 12v rail

 

in which case you would use two cables to be able to use two separate rails

[Simon771]

1 minute ago, Enderman said:

one cable is enough

 

the only reason you might want to use two cables is if you have a crappy power supply that only only deliver a small amount of watts on a single 12v rail

 

in which case you would use two cables to be able to use two separate rails

Well my PSU only have 1 12V rail for 648W and 54 amps. Does that mean that single cable like this can use up to 54 amps?

[Enderman]

Just now, Simon771 said:

Well my PSU only have 1 12V rail for 648W and 54 amps. Does that mean that single cable like this can use up to 54 amps?

yes

[Windows7ge]

My power supply had the option to run one cable like that but for ascetic purposes I ran two cables. Anyone feel free to correct me but I think it has something to do with how warm the cable can get. Running one cable as oppose to two will result in the single cable getting warmer compared to two cables supplying power. If the PSU only has one +12V rail it doesn't really matter beyond that.