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Finariel

macrumors newbie
Original poster
Sep 19, 2018
5
0
Dear Community,

I'm very desperate now. I bought a cheap Mac Pro 3.1 some time ago and am currently upgrading.
To the initial situation and the hardware:

MacPro 3.1 with 2x2.8 Quad Xeon - With a 2600XT I upgraded to High Sierra with Dosdude Tool, installed 32 GB RAM, moved the SSD to a PCIe card and installed 32 GB Ram. I exchanged the graphics card for a flashed 8800GT.

Now I wanted to install a RX580. For the power supply I use this cable:
https://www.amazon.de/gp/product/B07GPBRWDX/ref=oh_aui_detailpage_o06_s00?ie=UTF8&psc=1

When I start up, the card goes on / the fan starts running fast, but becomes quiet again. So far so good but I only get a white BIld (or a grey one? It already looks like it's showing something), but nothing more. Remote access from another Mac doesn't work.

Does anyone have an idea?
 
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What RX 580 are you using? Sapphire Pulse or something else?

Just in case the cable you got is bad, can you try w/ the single cable from the 8800GT? I know it's 6-pin, but it will still fit in (I believe) the leftmost 6 pins of the RX 580's 8-pin connector as you look at it installed, and it will work for short term testing.

EDIT: See post #11 below from @tsialex before doing this!
 
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Yes, i'm runnig the latest Version of High Sierra.

So how do i prevent this? Running the DosDude Patch again with the RX580 plugged in?! Sounds like a Problem with no Bootscreen and no Screen at all?!
 
No, Remote isn't working at this point.

Another GPU? What do you mean? Pluging in the RX580 and the 8800GT the same Time, both only plugged to one Mini 6pin (altough the RX580 needs two) ?
 
No, Remote isn't working at this point.

Another GPU? What do you mean? Pluging in the RX580 and the 8800GT the same Time, both only plugged to one Mini 6pin (altough the RX580 needs two) ?

For just 2D desktop environment, single mini 6pin should be OK to power the RX580
 
For just 2D desktop environment, single mini 6pin should be OK to power the RX580
The first time he opens a heavy 3D app, will blow the logic board protection fuse. At least 3 people here had to replace the backplane feeding RX 580 with just one mini 6pin connector, @calmasacow was the last one (4,1>5,1).

I have one backplane with the blown fuse to repair, can't find the right one to buy and replace.
 
The first time he opens a heavy 3D app, will blow the logic board protection fuse. At least 3 people here had to replace the backplane feeding RX 580 with just one mini 6pin connector, @calmasacow was the last one (4,1>5,1).

I have one backplane with the blown fuse to repair, can't find the right one to buy and replace.

That config just for re-running the Dosdude patch. And that’s a 3,1. Also, that’s actaully a RX470, not really the Nitro+ RX580 if I read correctly.
 
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The first time he opens a heavy 3D app, will blow the logic board protection fuse. At least 3 people here had to replace the backplane feeding RX 580 with just one mini 6pin connector, @calmasacow was the last one (4,1>5,1).

I have one backplane with the blown fuse to repair, can't find the right one to buy and replace.

Oooooh, yuck. Glad to know that, but dang— I just figured it would shut down the machine if it drew too much power, not permanently damage it. I will edit my suggestion above.
 
Oooooh, yuck. Glad to know that, but dang— I just figured it would shut down the machine if it drew too much power, not permanently damage it. I will edit my suggestion above.
I have BootROM dumps from @calmasacow backplane and the one here, both are from the start of 4,1 production. Apple has two versions for 4,1 boards, maybe it's something that they improved on version 2. I'll check this when I have a v2 board on hand.
 
I have 2 MP4,1s...would a BootROM dump from one of them help you if it's v2? Where does one look to determine that?
Part Number:

Backplane Board
Ver. 1 661-4996
Ver. 2 661-5444

Screen Shot 2018-09-20 at 11.55.47.png
 
I have one backplane with the blown fuse to repair, can't find the right one to buy and replace.

May I know where is the fuse location? I didn’t realise there is a fuse on the logic board, and want to know more about it. Million thanks in advance.
 
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My 2 boards have the same markings. Cannot find the ordering # (661-...) on them, but the part numbers I did find are the same:

To the left of the CPU Tray connector: 820-2337-A
Bottom right of board under barcode: 631-1009

Would either of these help you?

EDIT: Checking serial #s shows approx. production dates of Mar 2009 and Aug 2009. So, I'm guessing these will be V1 boards.
 
May I know where is the fuse location? I didn’t realise there is a fuse on the logic board, and want to know more about it. Million thanks in advance.

I'll take pictures this weekend.

My 2 boards have the same markings. Cannot find the ordering # (661-...) on them, but the part numbers I did find are the same:

To the left of the CPU Tray connector: 820-2337-A
Bottom right of board under barcode: 631-1009

Would either of these help you?

EDIT: Checking serial #s shows approx. production dates of Mar 2009 and Aug 2009. So, I'm guessing these will be V1 boards.
Apple have order numbers and part numbers, it's so confused. Take pictures of both labels, left and right of the CPU tray connector and PM me, I'll check with mine over the weekend.
 
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