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FRONTPAGE Nvidia RTX 4090 Review: MSI’s Suprim Liquid X Tames Ada Lovelace

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Specs show 6 pcie cables and 2 eps on the old one from my link.. but no matter. An 850W PSU with only two PCIe outputs is silly!!!

IIRC, the adapter packaging with the card had a little paper with it with pictures stating not to do it.

Three cables, two connectors on each so six total PCIe on the 2018 version. 2021 version has two cables, two connectors on each, four total. I should use bold on the words cable vs connector - I'm not using them interchangeably :)

I did find the warning you mentioned, I didn't see it when unwrapping the adapter. I'm going to ignore it since Corsair definitely specs each PCIe cable at 300w and they're meant to have both connectors used.

tnNSRqo.jpg
 
I'm going to ignore it since Corsair definitely specs each PCIe cable at 300w and they're meant to have both connectors used.
Your call on that one... just glad it's a temporary config while you wait (we've seen these melt with 3090 Ti's before). :)

Sorry, yes...connectors/cables it's annoying how Corsair specs their shyte out, lol.
 
I went looking for more cables in the PSU box and there weren't any. The contents listing only said 2xPCIe cables - I think this is the version I have: https://www.tomshardware.com/reviews/corsair-rm850x-2021-power-supply-review

edit: I just read around and it looks like the RMx series is made to do two connections on one, it uses 16 gauge wire to the first PCIe connector and the PSU side connectors are rated for 300w. Corsair even sells a 600 watt 12VHPWR cable with only two connectors on the PSU side: https://www.corsair.com/us/en/Categories/Products/Accessories-|-Parts/PC-Components/Power-Supplies/600W-PCIe-5-0-12VHPWR-Type-4-PSU-Power-Cable/p/CP-8920284 - I think I'm fine for a few days :)
I have the same PSU. I just looked in the box and I only have 3 PCIe 6+2 connectors:unsure:
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Sooooo does this mean I'm gona need a new PS ?
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for a 4090
 
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Before you go all in, I'd email Corsair and ask them. There's specific instructions that tell you not to do that... but if you /they can prove it's good to 300W, then I don't see a problem with it. Not all are rated that high... and I'd offer a guess that not many actually are. Just because there are two connectors doesn't mean they can output all of the power they are rated for without repercussions. We saw this in previous generations using one cable with two connectors and there was failure on some. ;)

If your PSU has three PCIe cables/unique inputs on the PSU side, I'd use all three and only piggyback one to minimize the risk. That's still a "no no", but....yeah.

I take that back Mine is a Corsair RM850, not an 850x
You know you can edit your posts and add to them right?
 
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Thanks, Earthdog, I won't be piggybacking, IF I decide to go with a 4090 I'd buy the correct PSU. I like to do things right the first time and avoid problems. It won't hurt my feelings to move this PS over to my eight-year-old computer. It never ends :clap: :love:
 
Ok, what's the point of having dual 8 pins per cable if the instructions say not to use them?
Well, the instructions on the video card say not to use them that way... not the PSU. AFAIK, that's only with the PCIe 5.0 12VHWPR connector. Many 2:1 (connector:cable) weren't intended to provide 300W through one cable (without being out of spec).

If the PSU specifically states it can provide 300W+ through a piggybacked connector, then it should be good. But if it doesn't, I'm not sure I would use it without reaching out to my PSU provider first.
 
Card is running happily at +200 core, 90% power limit. I might turn the the power down a little more and turn the memory clock up a little, but memory junction is already running pretty hot (well, maxing around 85C - I know this is fine, but I want better) so I might keep that on default until I add some backplate heatsinks.

Cablemod sent me a bad 24 pin, so only the EPS and 12VHPWR are pretty so far :/

873PSsk.jpg
 
Nice! A lot of headroom on the core for yours... mine wouldn't do 100 MHz over in my testing. :chair:

If I was you, I'd try turning the rear fan around to intake and just let the rads on the top/bottom exhaust out of the case. That could lower CPU temps and perhaps the card too with a cooler backplate. Even though it's water cooled, the back of that card puts out a ton of heat (especially if you're going to add heatsinks to the backplate - why???).
 
I double checked, vram is hitting 75C. I'd still like to bring it down a little if I can. CPU is maxing around 65, fine with that. Heatsinks on the backplate is something I did to my hybrid 3090, it brought vram temps down nicely, especially with a thin Noctua mounted on them. They really help move heat away from the backplate.

The photo I posted above is a little misleading - it's actually taken from the top looking down at the rig. It's a horizontal motherboard layout:

b8EJb4q.jpg

The airflow arrangement is front/bottom intake, sides/rear exhaust. Total 200mm front + 2x120mm bottom intakes, 240mm exhausting AIO on each side, plus the 140mm rear exhaust. There's a vent in the bottom of the cabinet where the computer lives, and the dual bottom 120mm intake fans draw completely fresh air in from the floor level. The front intake is up against a screened door (it's a Salamander Sonoma 237 cabinet) as well, so fresh air from outside the cabinet is being pulled in by the 200mm NF-A20. Here's the same cabinet model, note vent on floor and screen front door:

6fZucSW.png

If I switch the rear to intake, it'll be pulling in warmer air from inside the cabinet. I have the back of the cabinet off, so it might be ok, but I'd rather keep a cold side/hot side thing going if I can.

edit: You can see the bottom intake fans here:

WCtod93.jpg

And the overall airflow concept here:

7RhsSnP.jpg
 
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