Jump to content
Search In
  • More options...
Find results that contain...
Find results in...
mardon85

Help with 8 pin GPU connections

Recommended Posts

Posted · Original PosterOP

I've got quite a small SFX case (Ncase M1) and an SF750 psu. It's got x2 double 6+2 8Pin connections. 

Am I best connecting two individual cables from the Psu to a 2080ti or just use one of the double connectors? Space is tight so if two individual cables are better I'll order some shorter custom ones. 

Link to post
Share on other sites
Posted · Original PosterOP

Corsair SF750 is the best SFX PSU you can get but I have no idea if it can keep up with a full size one. 

The Gigabyte Gaming OC which is on the way apparently has LED's by the Pcie connectors which will flash if the the supply is unstable so I guess I could try both. 

Link to post
Share on other sites

You can use one cable, or you can use 2. 

 

Theoretically there is a difference. Practically its not really. 

Link to post
Share on other sites

The 2080 Ti is a 250W card, so I'd recommend using two separate cables. For GPUs with a TDP above 225W, use two separate cables. 


 

Quote

Women. They are a complete mystery.

-Stephen Hawking

 

I think the hoomans put their builds here?

Why do you hoomans give your builds a name? Here's my build, which I shall call "Do as I Say, Not As I Do" (seriously, don't get this build)

Spoiler

Ryzen 1500X @3,925 GHz

Cooler Master Hyper 212 Evo + 2x ML120

MSI B350 Tomahawk Arctic

2x8GB Corsair Vengeance LPX 3000 MHz CL15 (Micron B-die) @2933 MHz

Sapphire Radeon R9 280 Dual-X @1120 MHz / 1450 MHz

120GB 850 Evo

120GB Kingston SSD

500GB WD Blue

Cooler Master Elite 430

Seasonic Prime Titanium 650W

Logitech G710 with Kailh Box Jade

Logitech G502

HyperX Cloud

And my laptop, which I shall call "If It's Stupid But It Works" (It can actually play CS:GO at 50 FPS, and Civ V at 25 FPS)

Spoiler

Lenovo Thinkpad L460

Intel Core i3 6100U

4GB (probably) DDR4 2133 MHz

Intel HD Graphics 520 0.3-1.0 GHz

128GB Samsung MZ7LF128HCHP

Corsair M65 Pro RGB (worst mouse I've ever had)

Sennheiser CX 5.00G

And here would be where I would put a picture of my cat. But apparently, images are not allowed here. So take this instead (*ΦωΦ*)

Hello fellow night theme users

Link to post
Share on other sites
5 minutes ago, seon123 said:

The 2080 Ti is a 250W card, so I'd recommend using two separate cables. For GPUs with a TDP above 225W, use two separate cables. 

There is enough powerheadroom on a single double 6+2 pin to not worry about. 

 

As that should per spec do 150w each at 300w total with no issues

 

Then there is the extra 75w from the PCIe slot. 

 

So at least per spec there isnt an issue (not that there havent been issues before)

Link to post
Share on other sites
18 minutes ago, GoldenLag said:

There is enough powerheadroom on a single double 6+2 pin to not worry about. 

 

As that should per spec do 150w each at 300w total with no issues

 

Then there is the extra 75w from the PCIe slot. 

 

So at least per spec there isnt an issue (not that there havent been issues before)

The connector on the PSU side is still an 8 pin. On both Seasonic and Silverstone's websites, you'll find that they recommend two separate cables for GPUs >225W, iirc. 


 

Quote

Women. They are a complete mystery.

-Stephen Hawking

 

I think the hoomans put their builds here?

Why do you hoomans give your builds a name? Here's my build, which I shall call "Do as I Say, Not As I Do" (seriously, don't get this build)

Spoiler

Ryzen 1500X @3,925 GHz

Cooler Master Hyper 212 Evo + 2x ML120

MSI B350 Tomahawk Arctic

2x8GB Corsair Vengeance LPX 3000 MHz CL15 (Micron B-die) @2933 MHz

Sapphire Radeon R9 280 Dual-X @1120 MHz / 1450 MHz

120GB 850 Evo

120GB Kingston SSD

500GB WD Blue

Cooler Master Elite 430

Seasonic Prime Titanium 650W

Logitech G710 with Kailh Box Jade

Logitech G502

HyperX Cloud

And my laptop, which I shall call "If It's Stupid But It Works" (It can actually play CS:GO at 50 FPS, and Civ V at 25 FPS)

Spoiler

Lenovo Thinkpad L460

Intel Core i3 6100U

4GB (probably) DDR4 2133 MHz

Intel HD Graphics 520 0.3-1.0 GHz

128GB Samsung MZ7LF128HCHP

Corsair M65 Pro RGB (worst mouse I've ever had)

Sennheiser CX 5.00G

And here would be where I would put a picture of my cat. But apparently, images are not allowed here. So take this instead (*ΦωΦ*)

Hello fellow night theme users

Link to post
Share on other sites
27 minutes ago, GoldenLag said:

There is enough powerheadroom on a single double 6+2 pin to not worry about. 

 

As that should per spec do 150w each at 300w total with no issues

 

Then there is the extra 75w from the PCIe slot. 

 

So at least per spec there isnt an issue (not that there havent been issues before)

 

The problem is not that one cable can't deliver enough current, the problem will be that the high current provided by a single cable may heat up/overheat the cable itself.

Link to post
Share on other sites

Yeah, it's single-rail PSU, from power delivery side of things it doesn't matter if it's connected through one or two cables\connectors, but when such current are going only through one cable\connector it becomes a bit concerning, i vote for two cables too.


Tag or quote me so i see your reply

Link to post
Share on other sites
50 minutes ago, seon123 said:

The connector on the PSU side is still an 8 pin. On both Seasonic and Silverstone's websites, you'll find that they recommend two separate cables for GPUs >225W, iirc. 

indeed they do. still, im just saying that the spec says it shouldnt be an issue. 

 

48 minutes ago, Sir0Tek said:

 

The problem is not that one cable can't deliver enough current, the problem will be that the high current provided by a single cable may heat up/overheat the cable itself.

then that would be an issue with the cable not being able to handle spec, wouldnt it. 

 

i am aware of cable burnthrough on high current singlerail PSUs, where it has happened that the current throughput is way higher than spec. 

Link to post
Share on other sites
Posted · Original PosterOP

Thanks for all the replies everyone. 

Good point regarding the heat over time through the cable. 

I'll go with one for now so I can fit it all in and am awaiting a response to an email regarding custom ones. 

I'm hoping 25/30cm should be long enough without too much left over. 

Unless anyone has seen any already made up for sale in the UK that aren't £20 a go! 

Link to post
Share on other sites
1 hour ago, GoldenLag said:

indeed they do. still, im just saying that the spec says it shouldnt be an issue. 

 

then that would be an issue with the cable not being able to handle spec, wouldnt it. 

 

i am aware of cable burnthrough on high current singlerail PSUs, where it has happened that the current throughput is way higher than spec. 

It usually isn't a problem unless someone does use a single cable for a crossfire 2x Radeon rx 580 oc'ed setup, or similar. On the other hand, there's no harm to take the safe route.

Link to post
Share on other sites
36 minutes ago, Sir0Tek said:

I usually isn't a problem unless someone does use a single cable for a crossfire 2x Radeon rx 580 oc'ed setup, or similar. On the other hand, there's no harm to take the safe route.

well this time its about ordering custom cables if needed.

2 hours ago, mardon85 said:

Space is tight so if two individual cables are better I'll order some shorter custom ones. 

as seen here

 

45 minutes ago, mardon85 said:

Good point regarding the heat over time through the cable. 

its not heat over time, its more about sudden inrush of current which burns the connector. at least when it comes to your PSU

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×