The SATA power seems to be coming from one connector on the motherboard marked 'ODD PWR', can anyone confirm that? And dose anyone know the pinout for this connector? Plugging in a converter cable up in the optical bay and running it back down to the GPU seems a bit of a unnecessary hassle if I could just adapt the 6-pin directly from the 4 pin on the motherboard of the Mac Pro. 6-pin PCIe power has a max draw of 75W, so 108W from both SATA power cables should be easily enough, but since both SATA power plugs in the optical bay are powered by a single cable that splits in to two connectors, I would like to confirm this before I fry my board. If I calculated properly, I should be able to draw 54W from each SATA connector at 12v (1,5A per cable, 3 cables with 12V so total of 4,5a at 12V = about 54W). Would I be OK running the 6-pin on the card from the SATA power in the optical bay, and the 8-pin from both the mini 6 pins on the motherboard combined? Now my new machine (the 4,1) has SATA power in the optical bay, and the power spec for SATA is quite a bit lower than for the molex connectors. (the second connector on the motherboard is broken om my 2,1) Currently in the 2,1, the 8 pin on the card is being powered by the two molex connectors for the optical drives via a converter, and the 6 pin on the card is powered by one of the connectors on the motherboard. In the 2,1 I'm running a custom flashed radeon 7970 with 6+8 pin power connectors. The printed prototype works really well (at least for solid-state drives), but does tend to warp over time with the heat and uneven load.I just picked up a early 2009 4,1 Mac Pro to replace my current 2,1 Mac Pro. I want to find some shorter SATA cables, but overall I’m pretty happy with this. Well, you could buy that stupid 8TB drive and cage for ridiculous money, or you could do what I did and make some cables and a bracket to hold two SSDs. I found the appropriate plugs for the SATA power connectors and the 8-pin PCIe connectors (I didn’t get any 6-pin connectors).

Note that the front fans do not require a dust filter and dust will not accumulate. The PCIe connectors provide 12v and ground, and the SATA connectors provide 5v, 12v and ground (but curiously do not provide 3.3v, which is specified in the… specification… but which apparently most modern drives do not require). The 2019 Mac Pro features power connectors for both PCIe and SATA internal devices, but they are not standard connectors. 2019 Mac Pro Power Pinouts home shop work blog 2019 Mac Pro Power Pinouts 21 March, 2020 UPDATE: These are now for sale!

Sata power pinout