NattyKathy
[H]ard|Gawd
- Joined
- Jan 20, 2019
- Messages
- 1,601
3090Ti have the 12VHPWR internally split into 3 separate rails. The input section on all I've seen PCB images of looks basically the same as 3x8-pin cards and from what my MSI Gaming-X reports to HWiNFO / GPUz it's treating the power input as if it is 3 separate 8-pins with decent balancing.Add on to that, how does multiple rail power supplies respond when the different rails are shunted together in the connector? Need a power supply guru here.
From what I observed, previous GPUs with multiple pcie connectors had separate power circuity for each connector, while the new connector connects everything together so one power circuit in the card for the pcie connector. The 3090Ti didn't have this issue, so maybe a mute point. Unless the connector was split per 8 pin cable and not tied together like on the 4090. I don't know.
FE 3000-series have the same setup. My 3070Ti FE shows in software the "NVidia 12" or whatever we were supposed to call it as being 2x 8-pin and the input circuitry is duplicated like a native 2x8.
Lack of balancing on 4090 def seems like it could be part of the problem. Can't speak to how multi-rail PSUs would handle... Are true multi-rail PSUs still a thing? I haven't thought about those much since multi-socket SMP and SLI were the big thing in the 00s...