Having trouble finding a compatible PCIe Power Connector for dual GPU build

[rskill]

My new PC build has been freezing frequently when under heavy load, mostly when rendering models in Redshift which uses both GPUs (full build below). When I disable my second GPU, the freezes do not happen anymore. Especially considering how power-hungry the 3090 is (and this PC has two of them), this leads me to believe that the issue is with the power draw, but I could be wrong. The motherboard’s instruction manual recommends for dual GPU builds to connect a supplementary PCIe Power Connector cable from the power supply to the motherboard, but I’m having trouble finding the correct cable. Any help is greatly appreciated.

Photo from motherboard’s instruction manual: oc peg — Postimages

PC Build:
CPU: AMD Threadripper 3990X 2.9 GHz 64-Core Processor
CPU Cooler: NZXT Kraken Z73 73.11 CFM Liquid CPU Cooler
Motherboard: Gigabyte TRX40 AORUS XTREME XL ATX sTRX4 Motherboard
RAM: G.Skill Trident Z RGB 128 GB (4 x 32 GB) DDR4-4000 CL18 Memory
Storage: Samsung 980 Pro 2 TB M.2-2280 NVME Solid State Drive
GPU: Asus GeForce RTX 3090 24 GB STRIX GAMING Video Card x2
Case: Corsair 780T ATX Full Tower Case
Power Supply: Corsair AXi 1600 W 80+ Titanium Certified Fully Modular ATX Power Supply

[Bruce]

is it something like this you need;
[ATTACH type=“full” width=“139px”]9608[/ATTACH]
can’t see the mobo plug to make sure.
and does the graphics card port need a 6pin, 8pin or 2x6pins?

[rskill]

Hmm not sure. Looks like the cable you posted would fit, but not sure where the other side would go.

Here’s a pic of the “OC_PEG” port on the mobo:
[ATTACH type=“full” width=“162px”]9610[/ATTACH]

For the power cables going directly into the graphics card, each GPU takes 3x8 pins.
[ATTACH type=“full” width=“188px”]9611[/ATTACH]

[rskill]

SOLVED: AMD Threadripper 3990X 2.9 GHz 64-Core Processor only supports up to 3200 RAM speed which is likely what was causing the freezing. Also found the cable I was looking for:
[URL unfurl="true"]https://www.corsair.com/us/en/Categories/Products/Accessories-|-Parts/PC-Components/Power-Supplies/Type-4-Sleeved-black-PCIe-cable-with-pigtail-connector-and-capacitors-for-Type-4-PSU/p/CP-8920143[/URL]

[Bruce]

awesome.
nice and cheap too. (y)

will close as solved.