MP 1,1-5,1 XFX R580 No boot

[Cwheels123]

Good evening all, my first post here. I recently came into possession of a free 2009 Mac pro 4.1. If you’re interested, the specs are 8 core 2.26Ghz, 20gb of RAM (4x4 and 1x4 which I thought was strange!) and 4TB of hard disk space.

I have gone through the steps associated with bringing it up to 5.1, with High Sierra installed. Now, I have bought myself a AMD RX580 XFX graphics card to bring it upto speed. Once installed, there is no boot, no fan noise, no PSU noise. The only sign of life is this little red light which I can’t quite work out where it’s coming from.

I put the standard graphics card back in, boots up straight away. I am using two 6 pin mini to 6 pin, then two 6 pin to single 8 pin. These three wires are all from eBay.

So, any advice? Since buying the XFX, I have read about a lot of trouble with them. Did I not do enough research into the card, eBay wires not good enough or something else I am missing?

Thanks, Callum

 

[tsialex]

Install the RX 580 to a PC and confirm that the GPU works.

 

[avro707]

The cards also usually have two bios modes - one of them for mining, make sure that isn’t selected. It’s a very very small switch on the card.

 

[tsialex]

The cards also usually have two bios modes - one of them for mining, make sure that isn’t selected. It’s a very very small switch on the card.

Compute or Gamming mode does not make any difference in the OP situation, the Mac Pro does not even power on, to me what the OP describes is a short circuited GPU.

@Cwheels123 the red LED that becomes lit briefly when you press the power button on your video is one of the DIAG LEDs on the backplane diagnostic circuit, see the Apple Technician Manual, start around page 28 and go until page 38, to see the exact LED is the one that is being lit.

 

[nettmanek]

from what I heard, the XFX and Powercolor brands are not working the best with Mac.

also, as tsialex mentioned, try to use that card in any PC, see if it works at all.

 

[Cwheels123]

Hi guys, update. I got a better GPU power cable so the graphics card has a blue light on. The pc also boots as I hear the chime.

However, now I am getting a black screen. Any advice?

 

[Dayo]

I am getting a black screen. Any advice?

Check the vBIOS switch: https://forums.macrumors.com/posts/30429420

 

[nettmanek]

I would suggest plugging some original mac gpu(these are really cheap on eBay - like $30), to see boot screen etc. then once you confirm all is fine, swap the gpu and it should be ok