Powering GPU from separate PSU

[Digital]

So quick question, is it safe to do what Austin tried to do; power a GPU from a different PSU than what the system is using? I'm mostly just worried that the PSU is getting power from the motherboard, as well as from the separate PSU - could this lead to potential differentiates thus creating an current eventually frying the GPU, as the PSU's grounds are not connected?

 

Thanks in advance!

[Digital]

Like I just need a fast answer; Is it safe?

[Starelementpoke]

2 minutes ago, Digital said:

Like I just need a fast answer; Is it safe?

If you do it properly, yes.

[Digital]

1 minute ago, Starelementpoke said:

If you do it properly, yes.

Want to elaborate?

[EunSoo]

Can't see why it wouldn't be safe. The gpu will only be powered by the 2nd PSU (Don't think the PCI-e slot will power the gpu).

[Starelementpoke]

1 minute ago, Digital said:

Want to elaborate?

Don't really have the expertise to do so. Austin kinda just hot wired it and got lucky. In one of the Freegeek videos, there's cables you can use to do something like this.

[EunSoo]

1 minute ago, Digital said:

Want to elaborate?

Just make sure you look at/watch a guide to do it. I wouldn't just figure it out as you go.

[Naeaes]

7 minutes ago, Digital said:

Want to elaborate?

It's safe if you do it right. You need to short-circuit the green wire in the ATX12V connector to a ground in the same connector (any black wire). The risks lie in you shorting the wrong pins or overtaxing the PSU. If you hotwire it on like this, there's nothing but the built-in safeguards protecting the system from overvoltage and overcurrent. Those are more often than not too slow to react so if you intentionally overstress the PSU, it'll fry and gladly take your GPU with it. You know, if it was plugged into a PC instead, the PC would keep tabs on the voltages and shut down if they go over. So yeah. It's safe, if you do it safely.