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RTX 3080 and GTX 1080 TI PSU recommendation?

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dfonda

Senior Golfer
Joined
Feb 25, 2004
Anyone want to recommend a Beefy PSU with enough 8 Pin cables to run these 2 GPU's? It is the first PC in sig. The RTX 3080 looks like 3 8 Pins.

Currently have a Non modular 850W that is maybe 7 years old. It has been in 3 different builds and I want to set it aside for a spare. Also just want to get rid of some cables. Budgeting $200. (Or whatever;))

Maybe a 3rd GPU as an option? Using a ribbon cable? It is a 3 slot Mobo with a spot for a vertical GPU.

It is a folding PC hence the need to run the 2 or 3 GPU's.

Thanks for any advice.
 

EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
So, wait... you bought a 3080 with THREE power leads but want to get rid of wires? :p

Jokes aside, In order to have at least five PCIe power leads, you'll need to be in that 1KW+ range. A third GPU will likely push that need to seven, which I'd imagine is 1.2KW+ and pricey.
 
OP
dfonda

dfonda

Senior Golfer
Joined
Feb 25, 2004
So, wait... you bought a 3080 with THREE power leads but want to get rid of wires? :p

Jokes aside, In order to have at least five PCIe power leads, you'll need to be in that 1KW+ range. A third GPU will likely push that need to seven, which I'd imagine is 1.2KW+ and pricey.
It added to the urgency of the post..."Hey he has too many cables, must help him"

Don't you think?:D

FSP is still a good brand isn't it? 10 year warranty...

https://www.newegg.com/p/1HU-0095-0...000&cm_re=PSU_1000-_-1HU-0095-000H2-_-Product


https://www.newegg.com/evga-superno...SU_1000-_-17-438-160-_-Product&quicklink=true
 
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EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
I believe FSP is solid, but it varies by model. I'd confirm by searching for a review on that unit.

That said, the 1KW EVGA looks to fit the bill!! It has 8x 6+2-pin PCIe connectors so you're set there. I worry about the 1KW capacity with three cards though. Make sure you do the math on power use. Between these two cards, you're already looking at almost 600W between them. Add a third card like those and you may start pushing things on that KW PSU. :thup:
 
OP
dfonda

dfonda

Senior Golfer
Joined
Feb 25, 2004
I went with the EVGA. Shall see if it is enough. 3 8's for the 3080, 1 8 and 1 6 for the 1080 and an 8 for the 2060
 

EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
You can goto EVGA and order extra 8 pin cables.
That's fine for extras, but, if the PSU doesn't have the output for it, they won't do any good. Typically modular PSUs give you enough cables to fill up the ports on the PSU side. There isn't an extra port waiting to be used if you buy extra cables.
 
OP
dfonda

dfonda

Senior Golfer
Joined
Feb 25, 2004
Some of the review's mentioned plenty of cables as a plus, so there should be enough for at least the RTX 3080 and 1080 Ti.(That will be 5) I'll wait to see how much room is left and if there is one more for a 3rd GPU....and I really should have got the 1300W for that, it was only $50 more.

I would need to get a PCIe extender cable for the 3rd GPU. Next week I'll post a pic.

Still no hope of getting on Whitehawks threat list...That is going to take 2 or more 3080's.:sn:
 
OP
dfonda

dfonda

Senior Golfer
Joined
Feb 25, 2004
OK experts explanation needed...

https://www.newegg.com/evga-superno...&ranSiteID=Q1JB5HS2ifw-OlRRx4dP2jjSP.zPyMTcIg

It is in and I forgot to take a pic (as I was adding the GPU and PSU surreptitiously so as not to answer wifey's questions.):sn:

I was wondering how it had 8 PCIe's as listed in description with only 4 visible VGA ports. It came with 4 8 to 8 cables and 2 8 to 8 + 8 cables. They are all 6+2's so we can just call them 8's. So that comes to 6 with my math. More cables than ports...the other ports put out unusable power for VGA , I believe (CPU etc.)

Anyone know the output if they split the 8 into 2 8's? Is the 150W split into 75W and 75W? Even if it is split to 75W , The RTX 3080 is still getting 450W if it is a full 150W than the GPU gets 150x3 and 75W from the slot for 525W.

I did not need to but I tried 2 straight 8's into the RTX3080 and split the 3rd one into the RTX 3080 and an RTX 2060...Just to see if it would work...It does....

20 hours fah no failures full power limit (Fan's at 100%) .

Observations?

Here is a pic thru glass I forgot to clean, and usually have off...I wanted to see how hot things got. To show the cables.

The 3rd GPU I hoped to add is nixed the RTX 3080 is not only long (Which is no issue) in this case) but it surprisingly is so much wider it extends towards the glass side enough to block off the vertical mount. What I might try is to mount the 3080 vertical and 2 other GPU's behind it, and see if they all fit..but I digress...

PXL_20210126_201518135.jpg PXL_20210127_163115353.jpg
 
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EarthDog

Gulper Nozzle Co-Owner
Joined
Dec 15, 2008
Location
Buckeyes!
That PSU has a single rail for 12V, so it is all a big pool of power.

I would NOT split a single cable into two different cards. I guess it works, but, my gut tells me that's wonky.
 

torin3

Member
Joined
Dec 25, 2004
The 3rd GPU I hoped to add is nixed the RTX 3080 is not only long (Which is no issue) in this case) but it surprisingly is so much wider it extends towards the glass side enough to block off the vertical mount. What I might try is to mount the 3080 vertical and 2 other GPU's behind it, and see if they all fit..but I digress...

If you're going to get a riser cable for the 3rd card, this is the only style that worked for full production on my 1080s.

https://www.amazon.com/EZDIY-FAB-Express-PCIe3-0-Flexible-Extension/dp/B0778HNH29/
 
OP
dfonda

dfonda

Senior Golfer
Joined
Feb 25, 2004
I agree, but do they not list 8 Pcie ? I know I should have understood that 4 VGA must mean it can not support 8 but why do they list 8? What I am reading wrong? I am going to contact EVGA and get some clarification.

and T is that the longest extender you got to work 7.9"? Or is just that style and I can get a longer cable? I see they make a 12" ...

EDIT: Ok the spit 8 is fine, as you said E dog, it is one rail both the splits can carry 150 W , it is purely aesthetics whether to go with the split or the single. Even with 2 splits that only gives me 6 total (2 splits and 2 single 8's) You can see where 4 split cable would amount to 1200W and is why they only send 2 of them, if both used that would be 900W. I goofed up :screwy:needed the 1300W supply for only $50 more...I think I'll go ahead and order that one.

If I am lucky enough to get another 3080, I'll need to use this PSU in the other PC, it only has 2 slots. The PSU in that is barely enough for the 2 2060's

 
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torin3

Member
Joined
Dec 25, 2004
and T is that the longest extender you got to work 7.9"? Or is just that style and I can get a longer cable? I see they make a 12" ...

That style. It should say shielded. USB has nowhere near enough bandwidth, and the plain ribbon cable doesn't give you enough bandwidth for full production for folding.

https://www.amazon.com/LINKUP-Shielded-Twin-axial-Extension-Universal/dp/B07CS59X7Y/ This one is about a foot long, and there are links for some that are up to almost 5 feet long.

Also, I'm currently using 2 1KW PSUs for my main computer that is running 4 1080 cards. It doesn't need that much, but those are the high quality PSUs I had. I'm using a motherboard 24pin power splitter to combine their power.

However I've got each on its own 1500VA UPSs, but one is drawing more than that, because it keeps killing the batteries. I need to get a better single UPS, probably about 3000VA or more too take it over. I keep having one UPS crash due to bad batteries and having to reboot the system.
 
OP
dfonda

dfonda

Senior Golfer
Joined
Feb 25, 2004
That PSU has a single rail for 12V, so it is all a big pool of power.

I would NOT split a single cable into two different cards. I guess it works, but, my gut tells me that's wonky.
I'll remember this, I could not keep the power up splitting the 3rd cable. It worked for one week and then it kept lowering. That was at 450W

After going to seperate cables on that last cable it fixed the problem of lower power and therefore the OC was useful. 525W

It ran fine and was stable, but not at full capacity, gosh this card is a Hog.:shock:

Cable management sucks until I get 2 more single cables , I had to use 2 split cables , so their extra end is just hanging out.

The difference in science was 5.5 million to 7.2million running fah.

I am trying to figure out why it ran 7 million the first week than slowed down...I did change the monitor to the RTX 2060 ...Wanted to slow that GPU down when using the PC instead of the 3080. That was around the time power came up short....:shrug:
 
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