Please help a noob figure out what size PSU to order

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I bit the bullet and ordered 1 750w PSU.
Will suit me for now, for the next few years and if I need to upgrade again post 3080, so be it.

Shame I couldnt get a 140mm 850w PSU but I really dont mind that much.
Huge thanks to everyone for all the help. Learned a tonne in the last few months.
 
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Can you explain, would new PC's or just older PCs need to use cables from the PSU box? Why are you suggesting not to use existing cables?
Just keen to learn, thanks for your help.
Not all PSU manufacturers use the same pin layout. It’s possible to fry your components by using cables meant for a different power supply.
 
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Not all PSU manufacturers use the same pin layout. It’s possible to fry your components by using cables meant for a different power supply.
Just in case (on the remote off chance this is interpreted wrongly) it might be worth making it clear that the pins at the PSU side change. The pins at the HDD / MOBO / GPU side are obviously standardised!
 
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Just in case (on the remote off chance this is interpreted wrongly) it might be worth making it clear that the pins at the PSU side change. The pins at the HDD / MOBO / GPU side are obviously standardised!
Thanks Blue, Eliagon, and everyone else.
Used new cables, managed to post first time!
The 140mm suggestion was a good shout.
Like the strong smell of all the plastic whilst changing the cables over :D
 
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When running PCIe cables from the PSU to, say, a 3080, is 2 cables enough.
Lets say the 3080 takes 3 cables (with 8 pins)

I installed the 750w psu
Ran 2 cables to it
The 2 cables both have 2 power connectors.

Can I use just 2 cables, if the 2080 I buy can take 3 cables?
I am not sure/cant remember how much power each cable, and the PCIe port deliver.

So I was thinking 1 cable plugs in to the 3080
The other cable plugs into the 3080 twice.
Just wondering if thats ok, if the card is the type which physically can take 3 cables.

Someone more intelligent than I could have worded that using a quarter as many words!
 
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Looking on Nvidia's site I think the 3080 takes 2 8 pin PCIe power cables, via some 12 pin adapter thing, so you should be fine, you'll just need to use both cables coming from the PSU, I wouldn't use the splitters really, putting the load over separate cables is usually better, even if technically one might be enough. They can get a bit warm if you run them at near capacity.
 
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Looking on Nvidia's site I think the 3080 takes 2 8 pin PCIe power cables, via some 12 pin adapter thing, so you should be fine, you'll just need to use both cables coming from the PSU, I wouldn't use the splitters really, putting the load over separate cables is usually better, even if technically one might be enough. They can get a bit warm if you run them at near capacity.
I believe some cards take 2 cables. Some can take three seperate cables.
But I belive its also possible to figure out whether 2 cables meets the power requirement.

I swear my Phanteks amp 750 came with 3 PCIe cables. I counted them.
A week after I installed it, I cant find the third spare cable.
Remember folk saying only use cables that come with PSU.

I assume new graphics cards always come with the cables necessary to hook them up to any pcu and that there is uniformity there, in the edges of the PCIe connectors.
 
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When running PCIe cables from the PSU to, say, a 3080, is 2 cables enough.
Lets say the 3080 takes 3 cables (with 8 pins)
So I was thinking 1 cable plugs in to the 3080
The other cable plugs into the 3080 twice.
Just wondering if thats ok, if the card is the type which physically can take 3 cables.

That will work fine. If you have the option to run three cables there's an arguament for that being best practice but you're not going to overload anything with the arrangement you propose.

I believe some cards take 2 cables. Some can take three seperate cables.
But I belive its also possible to figure out whether 2 cables meets the power requirement.

Remember folk saying only use cables that come with PSU.

I assume new graphics cards always come with the cables necessary to hook them up to any pcu and that there is uniformity there, in the edges of the PCIe connectors.

You always have to connect a cable to all the GPU connectors. Whether it needs the power or not it won't boot with one empty. You must always use the cables for your particular PSU.

Graphics cards don't tend to come with any cables although the 30 series FE cards come with an adapter for their new 12 pin proprietary connector.
 
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Hi there i have a question for you guys.

Earlier this year i purchased a used gaming PC, GPU is a GTX 1080, PSU is a Seasonic Focus+ Platinum 750W. When i purchased the PC, i did not think to ask for the spare PSU cables. Fast forward to last week, my RTX 3080 finally got delivered!

Great news but - the 3080 requires 3 x 8Pin(6+2) power cables. My current PSU only has 1 x 8pin connector coming from the modular unit. Thus i need 2 additional cables to plug in. The modular supply has 3x Empty CPU/PCI-E ports, however i need to buy the cables to go in and connect up to my 3080.

So... i ordered some cheap male-2-male cables from Amazon, standard 8pin (6+2) formation, however i then decided that good quality cables might be wise, so i order some Silverstone ones from OCUK. Now i read online that many say it is not wise to mix brands with the cables, and that i should source some Seasonic cables, or something like cablemod which is disclosed as compatible.

May i have your thoughts?

Thanks

PSU Link - https://seasonic.com/focus-plus-platinum#cables
 
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So... i ordered some cheap male-2-male cables from Amazon, standard 8pin (6+2) formation, however i then decided that good quality cables might be wise, so i order some Silverstone ones from OCUK. Now i read online that many say it is not wise to mix brands with the cables, and that i should source some Seasonic cables, or something like cablemod which is disclosed as compatible.
Only use cables you know are compatible with your PSU.

It's not worth a guess. The end that plugs into the graphics card is standard but the end that goes into the PSU isn't. If the pin outs from the PSU don't match the cable you use you'll fry your lovely new 3080.
 
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Only use cables you know are compatible with your PSU.

It's not worth a guess. The end that plugs into the graphics card is standard but the end that goes into the PSU isn't. If the pin outs from the PSU don't match the cable you use you'll fry your lovely new 3080.

Thank you - you may have prevented me from a one way ticket to Wreck city.
 
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Should my phanteks 750w psu have come with 2 or 3 PCIe cables, would you guys guess, based on current trends?

I am sure I had 3 PCIe cables.
But only use 2 and now cant find the third after istallation.

Everything works. If I have 2 PCIe cables (both of which have 2x 8 pin connectors at the end) then I dont think I need to worry about getting a third separate cable (which I thought I had) for one day when I get a 3080.... i guess.
 
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