XT and TI. 2x 8 pin vs 3x 8 pin.
His concern is the daisy-chain. He only has 2x open PCIE cables and not 3x thus want to use +1 tail.
That is fine. Like I told him.
PCIE is a 150W cable. 70W from the slot. 5070 TI needs 300.
Old PSU's simply split the cables. They were not overrated. New PSU's do not, they are better rated to supply 150W direct + link.
Nvidia for 2 generations now don't load balance anymore. Cables as such, very important, hence his question of 2x vs 3x.
The issue is not the PSU. The issue is the PCIE cables. Nvidia knows this, that's why they made a new cable.
Hence, not recommended.
Similar example - you can daisy-chain 4x fans on the same connector. Guess what happens when you add fan number
You made it clear you don't grasp single rail and what load balancing means, yes for a PSU from the 2000's you had issues with dasiy chaining. With a single rail 12volt power supply, you can connect 20 fans to a single molex connector if you wanted to, consider fans are 12 volt and do not use the 3.3 and 5volt rails on the standard old 4 pin molex.
With a single rail you can connect as many fans to a single molex till the connector melts, it will take awhile as the amps drawn per fan is pretty low, you are more likely to trip the OCP from drawing too much before being able to melt a connector.
Sigh. FFS !
Just FYI, PCI-Sig specification state graphics cards can expect 150watt from PCIe cable. It isn't actually what the cable is able to handle, it is more to do with the cable wire gauge and old multi rail powersupplies. Shyte power supplies offered the bare min and even often below that.
The specification was from the 2000's, when multi rail PSU's were still a thing. Do you even understand what that means, it means the power supply would take the 12 volt rail in split it in to 2 - 4 separated rails each with their own current protections and wattage allowed per rail before protections kick in. 12 volt CPU connector was on its own rail, motherboard was on its own rail, and pcie was on a rail and each cable after that.Some times the pcie had more than one cable but shared a rail.
A Single rail power supply, the entire rail provides the full rated wattage in a single rail, GPU, CPU and motherboard all draw from the exact same rail and pool.
Nvidia didn't make the cable, PCI-SIG did, dell and nvidia sponsored the development of the cable, intel added it to ATX 3.0.
The pcie 6 and 8 pin 75watt and 150watt is what the graphics card can expect to draw not what the cable is capable of, the actual draw per cable is closer to 300watt, and it depends on the quality of the PSU and the wires and connectors.
I said the power draw is IRRELEVANT, because the power supply is SINGLE rail, besides that the adapter cable connectors while combined into a single connector if you actually follow the cables you would have spotted the cable splits the load between the two or three cables.
a Single 16-gauge wire can handle 104-130watts or 10 -13 amps at 12 volt, pcie cable is split over 6 or 8 wires, the power draw isn't limited by the rail or cables but by the connector, which is the weakest point. Terminals are almost always the weakest point in ANY electrical system.
pcie 12vhpwr has a 600 watt limit over 12 wires, ironically the weakest point is not the wires but the connector itself.
pcie is MORE than cable of providing 280watts over 8 wires, that is 35 watts per wire, split over two cables is 560watts.
And as I said the adapter cable already load balances between 2 or 3 cables it is well within specifications, in fact below them. With the power supply being a single rail it isn't a matter of power draw. Rather, if the rail protections can handle the spike loads. Neither the cabling nor the power draw is the issue. Spike loads is the issue pre ATX3.0 weren't designed to handle spikes loads and would trigger the OCP on power supplies.
Even with the adapter, 12vhpwr connector is still going to be the weakest point in that entire setup, because the connector is flawed in numerous ways. It was never about the power draw but the shitty connector.
