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kinless

macrumors regular
Original poster
Apr 2, 2003
205
379
Tustin, California
Howdy fellow Mac Pro nerds. Scrounged through these forums but couldn't find anything on the exact issue I'm having...maybe someone who has more knowledge than I can help point me in the right direction:

Mac Pro 5,1, latest 144.0.0.0, Mojave 10.14.6 (not using OpenCore or anything like that). Dual monitor setup with primary using DisplayPort, secondary using HDMI.

I purchased a "boot screen" Sapphire Pulse RX 580 8GB from DQupgrade (eBay). The card mostly works but there's one annoying hiccup. During macOS startup while using a DisplayPort monitor (either port), after the boot cycle is finished the screen goes blank then infinitely cycles between "Not Connected" and "Connecting" but never gets anywhere. Just prior to this I notice little horizontal pink line artifacts on the screen then the fans suddenly stop on the card. The infinite cycling issue also happens when waking the computer from sleep.

The workaround is to manually unplug and replug the DP cable from the card, which then brings up the macOS screen. (Sometimes it takes several attempts of unplugging/replugging to get it to work.) I have to do this after each restart/boot/wake-from-sleep into macOS.

This issue doesn't appear when using the HDMI ports. Also no issues with DisplayPort when booting natively into Windows via Boot Camp. Native boot picker using DP works fine as advertised. And of course my current GeForce GTX680 works fine using the same DP cable. It's only booting/waking into macOS via DP on the RX 580 when the issue surfaces. I've done SMC and PRAM resets which hasn't seemed to help at all. I don't know if it's a momentary power surge, or something in the startup process that's borking the DP handshake.

My first mistake was probably not buying directly from MVC, but their lack of response to my repeated email inquiries made me leery of making any purchase. My GeForce GTX 680 also came from DQupgrade, which I flashed myself and it's worked flawlessly the last few years, so I figured the RX 580 would be an easy decision. DQ has offered a full refund if I can't figure out this issue, so I'm not sweating that part. But I'd love to keep this card as I'm planning to purchase the upcoming Dell U3824DW (38" 3840x1600 ultra-wide) so need a card that can handle it.

Any ideas before I return this card? Thanks all!
 
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kinless

macrumors regular
Original poster
Apr 2, 2003
205
379
Tustin, California
Just to follow up, I bought some DP 1.4 and HDMI 2.1 cables from Monoprice to rule out connection issues. Primary monitor still goes black during boot/wake using DP so no dice there. But with the extra HDMI cable, my dual-monitor setup is now using both HDMI ports which all shows fine on boot/wake and seems to be the workaround for now.

I'd rather be using DP but we'll see how the incoming ultra-wide monitor fares with it...
 

h9826790

macrumors P6
Apr 3, 2014
16,651
8,575
Hong Kong
My suggestion is just return the card.

GTX680 Mac EFI UGA is coming form EVGA, that's a reliable manufacture with all the required info directly from Apple.

RX580's Mac EFI UGA is from MVC. He did a great job to make it work, however, extremely hard to make it as flawless as the GTX680 Mac EFI UGA.

Also, AFAIK, many people simply use hardware dumper to extra the MVC RX580 ROM (which may be developed from a MSI RX580 at the very beginning), then cross flash it to pretty much any RX580 (reference card, Sapphire PLUSE / NITRO+, XFX...). Even the card can boot, but the VBIOS part itself may be not 100% compatible at the very beginning.

Anyway, there is no need to buy any flashed card anymore. Just flash your Mac, then a RX580 with factory UEFI GOP ROM can show boot screen on the cMP.
 

kinless

macrumors regular
Original poster
Apr 2, 2003
205
379
Tustin, California
Anyway, there is no need to buy any flashed card anymore. Just flash your Mac, then a RX580 with factory UEFI GOP ROM can show boot screen on the cMP.

Thank you sir. Been following that thread now and again but the ROM flash process always seemed intimidating (I'm not a super low-level techie). Thought I would try the hands-off approach first but looks like if I want to make this work I'll just have to hold my nose and dive in. Probably not as complicated as it looks.

How would I know if an RX580 I want to purchase has the factory UEFI GOP on it? Is it just an unflashed PC card?
 

h9826790

macrumors P6
Apr 3, 2014
16,651
8,575
Hong Kong
Thank you sir. Been following that thread now and again but the ROM flash process always seemed intimidating (I'm not a super low-level techie). Thought I would try the hands-off approach first but looks like if I want to make this work I'll just have to hold my nose and dive in. Probably not as complicated as it looks.

How would I know if an RX580 I want to purchase has the factory UEFI GOP on it? Is it just an unflashed PC card?
Most "unflashed" cards are OK. Some of them may shipped with VBIOS but not UEFI GOP.

However, it's so easy to download UEFI GOP ROM for RX580 on the net now (e.g. from TechPowerUp. Or just ask the card's manufacture to send you one). Therefore, in general, for modern grahpic card, there is no need to worry if the card is shipped with UEFI GOP.

Also, there are generic UEFI GOP avail. You can always make your own UEFI GOP ROM for your card. Just like the old days what we did to the GTX680 / HD7950.
 

lancemcv1

macrumors regular
Jan 12, 2010
177
73
Most "unflashed" cards are OK. Some of them may shipped with VBIOS but not UEFI GOP.

However, it's so easy to download UEFI GOP ROM for RX580 on the net now (e.g. from TechPowerUp. Or just ask the card's manufacture to send you one). Therefore, in general, for modern grahpic card, there is no need to worry if the card is shipped with UEFI GOP.

Also, there are generic UEFI GOP avail. You can always make your own UEFI GOP ROM for your card. Just like the old days what we did to the GTX680 / HD7950.
I got a rx580 from DQupgrade to try installing Sonoma on my 5,1. They gave it to me and I will reach out to them. First I wanted to test the card so I installed it with your opencore package 1.0.0 and MOnterey 12.7.5 but the HDMI ports work and the display ports don't, and it seems the opencore bootloader is going out the Displayport and not the HDMI so the hdmi attached screen is black until the Monterey login screen appears. So maybe this card was flashed? I can try putting in my Mojave drive and boot without opencore but my 5,1 has enableGOP already in it so my problem is if I go to install OCLP I most likely will not get the bootloader at boot either. I guess I can reflash it with the original bios if it has been flashed and that might fix the issue. UPDATE: Just booted into Mojave after removing my opencore drive and the Diplayport works.
 
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h9826790

macrumors P6
Apr 3, 2014
16,651
8,575
Hong Kong
I got a rx580 from DQupgrade to try installing Sonoma on my 5,1. They gave it to me and I will reach out to them. First I wanted to test the card so I installed it with your opencore package 1.0.0 and MOnterey 12.7.5 but the HDMI ports work and the display ports don't, and it seems the opencore bootloader is going out the Displayport and not the HDMI so the hdmi attached screen is black until the Monterey login screen appears. So maybe this card was flashed? I can try putting in my Mojave drive and boot without opencore but my 5,1 has enableGOP already in it so my problem is if I go to install OCLP I most likely will not get the bootloader at boot either. I guess I can reflash it with the original bios if it has been flashed and that might fix the issue. UPDATE: Just booted into Mojave after removing my opencore drive and the Diplayport works.
Sounds Framebuffer issue in Monterey, please try this
 
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lancemcv1

macrumors regular
Jan 12, 2010
177
73
Sounds Framebuffer issue in Monterey, please try this
Thanks, So that worked and got the display ports working, but for some reason the Opencore bootloader does not show on any of the outputs, as well as not showing EnableGOP when booting into just Mojave drive wihtout opencore. I did see the tail end of the Apple bootloader in Mojave when trying the DVI port but it was just the tail end of it, I am guessing I need to flash the original bios back to the card not sure if it was modded? Also the DVI port is displaying weird colors but all the other ports are normal. could be the dvi to hdmi adapter I'm using, but I dont care about DVI any way. Thanks for your help. I also tried both bios positions and still no bootpicker... It's a Saphire Pulse 8 gig
 
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h9826790

macrumors P6
Apr 3, 2014
16,651
8,575
Hong Kong
Thanks, So that worked and got the display ports working, but for some reason the Opencore bootloader does not show on any of the outputs, as well as not showing EnableGOP when booting into just Mojave drive wihtout opencore. I did see the tail end of the Apple bootloader in Mojave when trying the DVI port but it was just the tail end of it, I am guessing I need to flash the original bios back to the card not sure if it was modded? Also the DVI port is displaying weird colors but all the other ports are normal. could be the dvi to hdmi adapter I'm using, but I dont care about DVI any way. Thanks for your help. I also tried both bios positions and still no bootpicker... It's a Saphire Pulse 8 gig
Correct, if no boot picker show up, you should able to fix that by flashing a factory ROM back in.

For dual BIOS card, that's very safe.
 
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lancemcv1

macrumors regular
Jan 12, 2010
177
73
Correct, if no boot picker show up, you should able to fix that by flashing a factory ROM back in.

For dual BIOS card, that's very safe.
So after a lot of messing around with different versions of AMDBflash I was able to flash the RX580 with version ATI flash 2.93 with an original rx580 bios, I had to use the old version as the flash process would stop with an error, saying missmatch… seeing the bios on the gpu had been modified and didn’t match the one I was installing the newer versions of AMDBflash would not install the bios. So long story short, I now have the bootscreen and display ports working on the rx580 with the 5,1. Thanks for the help.
 
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