RX580 Connection issues

G1NJ4N1NJ4

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Aug 29, 2020
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Hi, bit of a noob question, but we all have to start somewhere right..haha I have a 700w psu with 1 8 pin pcie connector, I purchased a RX580 (without checking the connections, i know bit of a noob moment haha) that needs 1- 8 pin and 1 - 6 pin, anyway I connected the only 1-8 pin and it booted up and installed all the drivers... my question is.. is it okay and safe just to use the 1 connector or is it a new Psu time? Thanks
 

Mylex

Gawd
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Aug 30, 2018
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If it has two connectors then you should use both of them, it can cause instability if it becomes power starved expecting to be able to get the full voltage both will feed it. Shouldn't be an issue until you actually put a load on it. Just desktop and web use shouldn't be an issue but why? Just connect the other port. You may have another connector available possibly rolled into a bundle, just do a check before going to replace the PSU, but if you don't I would replace it with one that has the connections you need.
 

pendragon1

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^^yup
Hi, bit of a noob question, but we all have to start somewhere right..haha I have a 700w psu with 1 8 pin pcie connector, I purchased a RX580 (without checking the connections, i know bit of a noob moment haha) that needs 1- 8 pin and 1 - 6 pin, anyway I connected the only 1-8 pin and it booted up and installed all the drivers... my question is.. is it okay and safe just to use the 1 connector or is it a new Psu time? Thanks
thats enough juice to power up the gpu but will not be enough for it under a proper load. like mentioned make sure you dont have another 6 pin stuffed somewhere. if not you can get by with a molex to 6pin adapter from amazon. its not preferred but will work. also check there isnt one in the gpu box...
 

RazorWind

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Are you sure your power supply only has one 8 pin PCI-E power connector? Unless it's very old, it would be pretty unusual for a 700W power supply to only have one these days.

Edit: As others have said, it's not the best idea to try to run this card on just one of the power inputs. You'll need to figure out a solution to connect the other one before you use it in anger.
 

funkydmunky

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Ya just buy a cheap 6pin power adapter, but yes very strange you PS does not have a couple of 6pins.
 

G1NJ4N1NJ4

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Aug 29, 2020
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yeah its only has 1 8 pin... i did buy a couple of molex to 6+2 pin adaptors from amazon but none of them worked, it just wasnt starting up.
 

T4rd

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Best way to know is to load the card to 100% with a benchmark or game to see if there's any instability. If it holds for several minutes without any issues it will probably be fine, but def recommended to just get a cheap molex adapter as you already have to ensure there's no issues.
 

RazorWind

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Best way to know is to load the card to 100% with a benchmark or game to see if there's any instability. If it holds for several minutes without any issues it will probably be fine, but def recommended to just get a cheap molex adapter as you already have to ensure there's no issues.
Don't do this!

Most graphics cards actually wire up half of the VRM to one power connector, and the other half to the other. Nvidia cards have elaborate balancing circuitry to keep the connectors' input current at the proper ratio, but many AMD cards don't, and just wire the connectors up directly. I've not done much testing to see what happens when you just leave one connector unplugged, but if the card doesn't have a mechanism for checking for this built in, as many AMD cards apparently don't, you run the risk of either blowing the fuses on the card, necessitating a repair, or loading half of the VCore VRM at double its intended capacity. It might survive just fine, but it also might not.

The real solution here is to rig up a power supply to that 6 pin connector so everything works properly. G1NJ4N1NJ4, can you post a photo of the adapters you bought, and how they're connected? That's a pretty simple thing to hook up - you shouldn't be having any problems with that.
 

T4rd

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Don't do this!

Most graphics cards actually wire up half of the VRM to one power connector, and the other half to the other. Nvidia cards have elaborate balancing circuitry to keep the connectors' input current at the proper ratio, but many AMD cards don't, and just wire the connectors up directly. I've not done much testing to see what happens when you just leave one connector unplugged, but if the card doesn't have a mechanism for checking for this built in, as many AMD cards apparently don't, you run the risk of either blowing the fuses on the card, necessitating a repair, or loading half of the VCore VRM at double its intended capacity. It might survive just fine, but it also might not.

The real solution here is to rig up a power supply to that 6 pin connector so everything works properly. G1NJ4N1NJ4, can you post a photo of the adapters you bought, and how they're connected? That's a pretty simple thing to hook up - you shouldn't be having any problems with that.

Wow, good to know I guess and I would have thought the card would be designed so that it won't damage itself just because of a potential loose or missing PSU connection. Seems like quite a design flaw if that's the case. Personally that would make me more interested to try it out though, lol.
 

G1NJ4N1NJ4

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Aug 29, 2020
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i bought 2 sets of adaptors, 1 molex to 8 pin and a adaptor that converts my 8 pin to 2x 6+2 pin.... and not 1 of them works. so i have no idea... the PSU i have is a CIT builder 700w. thanks.






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pendragon1

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why?! get a molex to 6 pin. or i guess since you got it, connect it to the 8pin and use the pus 6pin(take the two pins off).
edi: cancel that. that is a scam psu like described above*. there is no way a 700w psu is $25. get a new proper, brand name psu befor you kill your gpu.
https://www.amazon.co.uk/CiT-700W-E...0829G8TRX/ref=cm_cr_arp_d_product_top?ie=UTF8
*edit: might be confusing another thread. its a low watt psu thats been over rated.
 
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G1NJ4N1NJ4

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yeah i thought that, im not using the PSU at the moment as i took it out of my PC, im not using it until i get a proper brand PSU.... also never let your wife buy you a PSU...lol
 

SAVIOR02

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Sep 27, 2020
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Hi, bit of a noob question, but we all have to start somewhere right..haha I have a 700w psu with 1 8 pin pcie connector, I purchased a RX580 (without checking the connections, i know bit of a noob moment haha) that needs 1- 8 pin and 1 - 6 pin, anyway I connected the only 1-8 pin and it booted up and installed all the drivers... my question is.. is it okay and safe just to use the 1 connector or is it a new Psu time? Thanks
Dude dont listen to these guys. I have the rx580 special edition and I ran it with both cables vs just the 8 pin and after thorough testing I only use the 8 pin. Seems to work the same if not better for me because both draws more power and I only have a 600 watt PS with an over clocked 4.6 processor. Plus it seems to form less heat as well on the card. To me the two pins are there only if you don't have the other. I had just bought a 5500 xt and it only had a 8 pin and they are both very similar cards. I ended up returning it not really an upgrade.
 

SAVIOR02

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yeah i thought that, im not using the PSU at the moment as i took it out of my PC, im not using it until i get a proper brand PSU.... also never let your wife buy you a PSU...lol
So pretty much installing the extra 4 pin doesnt do anything. You wasted your time and money not to mention headache.
 
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