[SOLVED] Upgrading from RX480 (6+2 pcie) to GTX 1080 (6+2 pcie) "please connect pcie power"

[DemonDrex]

Hello, I have been given a GTX 1080 to replace my RX480, tried to swap it out, both have 6+2 pcie connectors so should be a simple swap, however when connecting the new card i get the "please connect pcie power" notification on boot, the RX480 works fine without issue so its not the cable and the GTX1080 was working when last installed on my friends pc, I have a corsair CX430m (i know this is cutting the limits close) but it should still boot right? i have seen a lot of posts on this error but its almost always a cable issue and havent seen anything that has helped so apologies if its already been solved but i cant find a soloution so far, thanks all

 

[Eximo]

Which 1080? And what are the rest of the system specs?

And yes, I would not trust a 430W supply with a 1080. Even the base model is 180W and you are looking at a 384W 12V rail, when the PSU was new minus whatever your total system requires at 12V.

I wouldn't rule out a cable fault. Your RX480 might have been fine with only the 6-pin technically working, 8-pin was a precaution on the part of AMD since it was riding the 150W edge of what a 6-pin and the slot could provide. GTX1080 will insist on a full 8-pin connection. That means 3 12V+, 3 GND, and two Sensor Wires.

You can verify that since the CX430m has color coded cables, You want to see 3 yellow wires in the six-pin connector. The +2 just carry a sense wire and ground to inform the system that the 6-pin portion does carry 3 12V wires.

 

[DemonDrex]

Which 1080? And what are the rest of the system specs?

And yes, I would not trust a 430W supply with a 1080. Even the base model is 180W and you are looking at a 384W 12V rail, when the PSU was new minus whatever your total system requires at 12V.

I wouldn't rule out a cable fault. Your RX480 might have been fine with only the 6-pin technically working, 8-pin was a precaution on the part of AMD since it was riding the 150W edge of what a 6-pin and the slot could provide. GTX1080 will insist on a full 8-pin connection. That means 3 12V+, 3 GND, and two Sensor Wires.

You can verify that since the CX430m has color coded cables, You want to see 3 yellow wires in the six-pin connector. The +2 just carry a sense wire and ground to inform the system that the 6-pin portion does carry 3 12V wires.

its a geeforce founders edition 1080, and yes the cable has the 3 yellow wires in the 6 pin.

 

[DSzymborski]

I wouldn't rule out a cable issue, but since I wouldn't be using this PSU even with the old card -- why is an ancient entry-level PSU powering expensive hardware -- it's not even worth worrying about until the PSU is replaced.

 

[DemonDrex]

update: upgraded PSU and issue solved, thank you.