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typecase

macrumors 6502
Original poster
Feb 2, 2005
394
400
Hello all,

I'm upgrading a noisy 5870 in a Mac Pro 5,1 running Sierra 10.12.6 to a RX580. I've read the threads below and got the eGPU recommended Sapphire Pulse RX580. It's coming Thursday. Despite reading those threads, I'm still a bit confused as to what cabling I will need. Can I use the cables from my 5870 and plug it into the new card?

If not, are there any cables I can get on short notice to get this in the computer soon? The noise from this fan is driving me nuts. The cables recommended in one of the threads ship from china so I probably won't see them for two weeks at minimum. The other one mentioned from amazon is unavailable:

Will this work?:
https://www.amazon.com/gp/product/B00PVJ2DNC/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Any help greatly appreciated.

Threads I've read :
https://forums.macrumors.com/threads/2012-mac-pro-sapphire-pulse-radeon-rx-580.2065814/
https://discussions.apple.com/thread/4509919
https://forums.macrumors.com/threads/amd-polaris-gpus-plug-and-play-in-macos-10-12-6-10-13.2050945/
 

t8er8

macrumors 6502
Dec 4, 2017
252
100
Quebec, Canada
Hello all,

I'm upgrading a noisy 5870 in a Mac Pro 5,1 running Sierra 10.12.6 to a RX580. I've read the threads below and got the eGPU recommended Sapphire Pulse RX580. It's coming Thursday. Despite reading those threads, I'm still a bit confused as to what cabling I will need. Can I use the cables from my 5870 and plug it into the new card?

If not, are there any cables I can get on short notice to get this in the computer soon? The noise from this fan is driving me nuts. The cables recommended in one of the threads ship from china so I probably won't see them for two weeks at minimum. The other one mentioned from amazon is unavailable:

Will this work?:
https://www.amazon.com/gp/product/B00PVJ2DNC/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Any help greatly appreciated.

Threads I've read :
https://forums.macrumors.com/threads/2012-mac-pro-sapphire-pulse-radeon-rx-580.2065814/
https://discussions.apple.com/thread/4509919
https://forums.macrumors.com/threads/amd-polaris-gpus-plug-and-play-in-macos-10-12-6-10-13.2050945/
Yeah that one from the 5870 won’t work, you need a mini 6 pin to 8 pin pci power cable, The gpu requires an 8 pin pci power cable and the Mac Pro has 2 mini 6 pin power ports. That one you asked if it would work should be just fine.
 

handheldgames

macrumors 68000
Apr 4, 2009
1,943
1,170
Pacific NW, USA
No. The cable you suggested only supplies 75 watts + 75 watts from PCIe. The RX580 wants 225 watts. You need BOTH PCIe power lines: 75+75 + 75 from PCIe.

This $12 cable should provide what you need.

You can read more on this MacPro PCIe power draw oriented post

s-l1600.jpg
 
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DaveGee

macrumors 6502a
Jul 25, 2001
677
2
wait the 5870 is already in the Mac Pro if yes then those cables should work fine I would think
 

handheldgames

macrumors 68000
Apr 4, 2009
1,943
1,170
Pacific NW, USA
wait the 5870 is already in the Mac Pro if yes then those cables should work fine I would think

The OP needs an 8-pin connector delivering 150Watts. The 6-pin connectors deliver 75 watts each. Considering the price of the GPU, a $12 cable should be a given.

While a rx480 can get by on a single 6pin power cable (75w) + PCIe (75w) at 150 watts, max power consumption on the rx580's 8-pin connector has been increased to 150 watts. Any draw > 75 watts from one PCIe power line is pushing the logic board power traces beyond spec and towards failure.
 
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DaveGee

macrumors 6502a
Jul 25, 2001
677
2
The OP needs an 8-pin connector delivering 150Watts. The 6-pin connectors deliver 75 watts each. Considering the price of the GPU, a $12 cable should be a given.

While a rx480 can get by on a single 6pin power cable (75w) + PCIe (75w) at 150 watts, max power consumption on the rx580's 8-pin connector has been increased to 150 watts. Any draw > 75 watts from one PCIe power line is pushing the logic board power traces beyond spec and towards failure.

gotcha and yes the price of the card vs a new cable is a no brainer :) I just popped in a gtx 970 (pc card) and it actually came with a 6 to 9 pin adapter and I used that and it works tho I have not exactly stressed the card yet so yea...
 

MarkC426

macrumors 68040
May 14, 2008
3,690
2,093
UK
Thanks for the information. I ordered it. It looks like it will only get here mid-July. Sigh.
Was that the estimate from ebay china?
I got mine from china, had a long delivery estimate but arrived in about a week.
 

skizzo

macrumors 6502
Apr 11, 2018
260
83
Thanks for the information. I ordered it. It looks like it will only get here mid-July. Sigh.

Yeah that sucks. That is the reason why I ended up using two mini 6pin to standard 6pin cables, with a dual 6pin female to single 8pin male cable. Overall it is more costly by around $20 but since I already had one mini 6 to standard 6 it made some sense for me. I did not want to wait what was projected at potentially over a month ship date for a $15 cable lol
 

iGobbleoff

macrumors 6502
May 2, 2011
354
469
I think I got the same cable, but looking on ebay, its already shipped, but still says arrival would be a month away. I'm not fussed, I can wait, but I think its going to get here in the next couple of days
 

handheldgames

macrumors 68000
Apr 4, 2009
1,943
1,170
Pacific NW, USA
I think I got the same cable, but looking on ebay, its already shipped, but still says arrival would be a month away. I'm not fussed, I can wait, but I think its going to get here in the next couple of days

There are some serious issues using these cards detailed starting in Post #25.

Bottom line... Using a RX580 with stock BIOS can fry your mac. Just read post #24 in the same thread from today.

If you have a RX580 it's probably best that you under-volt the card to protect from burning out your MacPro.

General Info on how to undervolt
[GUIDE][TUTORIAL][XMR,ETH,ETN]How To Mod Bios RX470/570/480/580 VEGA Mining

A guide specific to Mac setup process. One tools are setup, use undervolt info from the above link.
Flash Your RX 470 Card on Mac / Linux
 
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