Max current per molex string?

[pinchthings]

Hi,

I have a computer I'm tinkering with for some hobby cryptomining. My old gaming rig has a Corsair CMPSU-750TX PSU (single 12V rail @ 62A, 750W total). For my desired end state with 4x GPUs (3 of which will be on molex powered risers), I happen to be one PCIE 6pin short. To do this, I would need one of the 2 molex->6pin Y adapters. This PSU happens to have 2 strings with 4 molex connectors each to power the risers and this adapter.

While I physically have enough plugs and the total current draw/power is under the ceiling for this PSU, I am worried about overloading the molex cables. This is what would be on each molex string:

String 1:
Molex to riser to GTX 1060
Molex to riser to GTX 1060
1/2 of the molex to 6pin splitter to GTX 1060

String 2:
Molex to riser to GTX 1060
Other 1/2 of the molex to 6pin splitter to GTX 1060
120mm fan power

According to the web, GTX1060 runs at 120W at load. I've also read that PCIE slots (and by extension the external riser) takes 75W. So I am assuming the molex to 6pin Y adapter is 45W split across 2 molex. I don't know if this is how the power is really balanced.

So that math leads me to say that string 1 is 172.5W (14.4A) and string 2 is 97.5W (8.1A) . Alternatively I could put both molexes of the Y to 6pin on one string and the split would be a little more balanced at 12.5A and 10A, respectively. I've heard it thrown around that 10A is the spec on molex connectors, but I didn't know if that was the whole string or just one plug.

My net question is, is this current load on each molex string safe and are my assumptions correct?

Thanks

 

[VirtualLarry]

A string of molex connectors, can support 75W.

Edit: Srsly, time for a 1200W PSU.

 

[Rifter]

If its 18 ga wire it can handle 10 amps, at 12v thats about 120W. If its 16ga wire that will bump you up to the 150w range.

If its only 20ga dont even attempt this.