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Best way to connect RTX4090 power cables to PSU?

Associate
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Hi everyone, hoping for some advice. I can see that RTX4090 cards come with a 16 pin power connecter that then branches away to 4x 8 pin (I think) connectors. What is the best way to connect these to the PSU? Would each of these 4 connectors need a direct connection to the PSU?

Sorry if this is a silly question. I don't have the GPU yet, just thinking about it.

Thank you.
 
Associate
OP
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Yes, Each of the 4x8pin connectors on the adapter needs a direct 8 pin PCI-E connector from the PSU.

Thank you. I think my Seasonic Focus GX PSU only has provision for 3 direct 8 pin connectors - I will have a good look tomorrow. Would it be ok to daisy chain one of them? (Each direct PCIe cable has 2x 8 pin connectors).
 
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Associate
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Thanks for the replies. I am looking at the Corsair HX1200 and I can see that Corsair now produce a 12VHPWR cable for some existing models (part: CP-8920284). However, I can see this only connects to 2x 8 pin PCIe connectors on the PSU. Is this safe? Are 8pin connectors not usually rated at 150w each?

Also, despite the Gigabyte OC 4090 coming with a 600w 12VHPWR to 4x 8 pin adapter, would it not only pull around 450w in stock operation? I don’t plan on any over clocking. So wondering again if daisy changing the 4th 8pin cable on my PSU (only 3x 8pin sockets) would actually be ok?

Anyhow, these are just questions to help me understand a little more. I think the safest bet would be to go for something like the Corsair HX1200 PSU and use the adapter cable that comes with the GPU.
 
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Associate
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The PCI/CPU ports on most PSU’s supply up to 300watts per port so 2x should be fine. I’ve still got a 4x to 12VHPWR cable coming from Cablemods though, just for extra redundancy.
 
Soldato
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It is confusing. I've got the 4090 FE and Corsair RM850 I've the Corsair cable with 2x8pin and the cablemod 3x8pin and I was confused as you. I'm going to try the cablemod first. I'll be buying a decent new psu eventually probably ATX 3.0 when I can but in meantime I'm confident my current psu and cables will do the job.
 
Soldato
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It is confusing. I've got the 4090 FE and Corsair RM850 I've the Corsair cable with 2x8pin and the cablemod 3x8pin and I was confused as you. I'm going to try the cablemod first. I'll be buying a decent new psu eventually probably ATX 3.0 when I can but in meantime I'm confident my current psu and cables will do the job.

The Cablemod cable for the 4090 should be 4x8 pin, If yours is 3x8pin then that is the cable for the 4080 according to their site.
 
Soldato
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The best way to connect is to make sure that the small 12VHPWR is inserted fully. Either hear a click or make sure you visually confirm that the connectors are FULLY inserted.

If available get a PSU with a dedicated 12VHPWR connector - as current 3:1/4:1 'adapters' look like a snakes wedding.
 
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