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expede

macrumors regular
Original poster
Jan 15, 2018
236
67
Sweden
Hi!

I have been reading this great site and found, to my surprise that the Mac edition of my Sapphire 7950 GPU got a switch on the side. I found this text on Sapphire homepage;

It has Dual Firmware support via a simple Firmware (Dual BIOS) switch. In one position the Sapphire HD 7950 MAC Edition supports Mac OS X/Windows under non-UEFI compliant mode and in the other it supports Windows with UEFI hybrid firmware enabled.

So I tried to follow some tutorials on this forum, to be able to install Windows 10 prof in EFI-mode on my Mac Pro 5,1 (2012). I pulled all disks except my SSD in bay 1. This went smooth until the last boot and I did the last finish (preference) and the home screen was shown in 0,5 sec then the screen went black. Totally unresponsive. No luck with rebooting. I got mad and reinstalled windows in ordinary old fashion way (non-EFI).

So my question is;

Is this switch the reason it didn't work? Maybe this is a stupid question. I am just a user.

Mac Pro 5.1 (2012), 28GB, Sapphire 7950 White Mac Edition.

Best regards

/Per
 

LightBulbFun

macrumors 68030
Nov 17, 2013
2,808
3,125
London UK
Hi!

I have been reading this great site and found, to my surprise that the Mac edition of my Sapphire 7950 GPU got a switch on the side. I found this text on Sapphire homepage;

It has Dual Firmware support via a simple Firmware (Dual BIOS) switch. In one position the Sapphire HD 7950 MAC Edition supports Mac OS X/Windows under non-UEFI compliant mode and in the other it supports Windows with UEFI hybrid firmware enabled.

So I tried to follow some tutorials on this forum, to be able to install Windows 10 prof in EFI-mode on my Mac Pro 5,1 (2012). I pulled all disks except my SSD in bay 1. This went smooth until the last boot and I did the last finish (preference) and the home screen was shown in 0,5 sec then the screen went black. Totally unresponsive. No luck with rebooting. I got mad and reinstalled windows in ordinary old fashion way (non-EFI).

So my question is;

Is this switch the reason it didn't work? Maybe this is a stupid question. I am just a user.

Mac Pro 5.1 (2012), 28GB, Sapphire 7950 White Mac Edition.

Best regards

/Per

sadly in my testing it seems the AMD Radeon HD 7950 when running with the Mac EFI is not compatible with windows booting in EFI mode.

in-fact before the fall creators update, the windows EFI Bootloader it self would crash when I booted it with my 7950 in EFI mode, and you could not even make it into the windows kernel.

the creators fall update fixed the boot loader issues but sadly the Radeon Drivers just fall over and die and BSOD the Machine with the GPU in Mac EFI mode.

so what I do is I boot into the boot selector, hold control down while clicking the "EFI Boot" Windows disk option this sets windows as the startup disk, while its booting I switch the BIOS switch over to the PC BIOS, let the Machine BSOD and reboot and then (booting blind) since im now running the PC BIOS it will then Boot windows 10 since the AMD drivers can handle a PC (UEFI/BIOS) card just fine with windows booting in EFI mode. (and once im done in windows I switch back to my Mac EFI and reboot the machine holding option and selecting OS X SSD of course)

I hope this helps (and indeed its quite convoluted but its the only way I have been able to EFI boot windows with my AMD Radeon HD 7950)
 

h9826790

macrumors P6
Apr 3, 2014
16,614
8,546
Hong Kong
sadly in my testing it seems the AMD Radeon HD 7950 when running with the Mac EFI is not compatible with windows booting in EFI mode.

in-fact before the fall creators update, the windows EFI Bootloader it self would crash when I booted it with my 7950 in EFI mode, and you could not even make it into the windows kernel.

the creators fall update fixed the boot loader issues but sadly the Radeon Drivers just fall over and die and BSOD the Machine with the GPU in Mac EFI mode.

so what I do is I boot into the boot selector, hold control down while clicking the "EFI Boot" Windows disk option this sets windows as the startup disk, while its booting I switch the BIOS switch over to the PC BIOS, let the Machine BSOD and reboot and then (booting blind) since im now running the PC BIOS it will then Boot windows 10 since the AMD drivers can handle a PC (UEFI/BIOS) card just fine with windows booting in EFI mode. (and once im done in windows I switch back to my Mac EFI and reboot the machine holding option and selecting OS X SSD of course)

I hope this helps (and indeed its quite convoluted but its the only way I have been able to EFI boot windows with my AMD Radeon HD 7950)

I never install Windows in EFI mode, but AFAIK, BootChamp can also boot EFI Windows, however SIP must be disabled.

Hi!

I have been reading this great site and found, to my surprise that the Mac edition of my Sapphire 7950 GPU got a switch on the side. I found this text on Sapphire homepage;

It has Dual Firmware support via a simple Firmware (Dual BIOS) switch. In one position the Sapphire HD 7950 MAC Edition supports Mac OS X/Windows under non-UEFI compliant mode and in the other it supports Windows with UEFI hybrid firmware enabled.

So I tried to follow some tutorials on this forum, to be able to install Windows 10 prof in EFI-mode on my Mac Pro 5,1 (2012). I pulled all disks except my SSD in bay 1. This went smooth until the last boot and I did the last finish (preference) and the home screen was shown in 0,5 sec then the screen went black. Totally unresponsive. No luck with rebooting. I got mad and reinstalled windows in ordinary old fashion way (non-EFI).

So my question is;

Is this switch the reason it didn't work? Maybe this is a stupid question. I am just a user.

Mac Pro 5.1 (2012), 28GB, Sapphire 7950 White Mac Edition.

Best regards

/Per

You mentioned about the ROM switch, did you actually keep the switch at the UEFI position (no boot screen) all the way through the process? As LightBulbFun stated, the Mac EFI is not compatible with the EFI Windows.
 

LightBulbFun

macrumors 68030
Nov 17, 2013
2,808
3,125
London UK
I never install Windows in EFI mode, but AFAIK, BootChamp can also boot EFI Windows, however SIP must be disabled.



You mentioned about the ROM switch, did you actually keep the switch at the UEFI position (no boot screen) all the way through the process? As LightBulbFun stated, the Mac EFI is not compatible with the EFI Windows.

indeed I have heard of boot champ, ill have to play with it at some point (But i also figured its worth pointing out the hold control when clicking on a disk at the boot picker to set it as the start up disk is worth mention, its one of those lesser known facts about 2008+ intel Macs :) its also very handy for setting weird disks as start up disks, like linux installs )

it is worth mentioning that newer Mac/flashed NVIDIA cards (GTX 680/Kepler and newer MVC cards AFAIK) are compatible with Windows in EFI mode but older NVIDIA cards from the Tesla arcutecture dont seem to like EFI mode windows the GPU drivers crash.

it seems in terms of modern cards only the AMD Radeon HD 7950 has this issue when in Mac EFI mode booting windows in EFI mode.

(IIRC the ATI Radeon 5770 works in EFI mode.)

it would be good to assemble a list of which Mac flashed/Mac EFI cards play nice with windows installed in EFI Mode...
 

expede

macrumors regular
Original poster
Jan 15, 2018
236
67
Sweden
Hi!

The answer is, for me, to complicated. I have an inferior education. But if I understand you correct, what I suggested was not correct? So I should leave the switch as it is. To the "right" then.

Thanks for you time and I am sorry for disturbing you!

Best regards

/Per

When I use Sierra High and Hi and thanks for the fast relpljasdf
I never install Windows in EFI mode, but AFAIK, BootChamp can also boot EFI Windows, however SIP must be disabled.



You mentioned about the ROM switch, did you actually keep the switch at the UEFI position (no boot screen) all the way through the process? As LightBulbFun stated, the Mac EFI is not compatible with the EFI Windows.
sadly in my testing it seems the AMD Radeon HD 7950 when running with the Mac EFI is not compatible with windows booting in EFI mode.

in-fact before the fall creators update, the windows EFI Bootloader it self would crash when I booted it with my 7950 in EFI mode, and you could not even make it into the windows kernel.

the creators fall update fixed the boot loader issues but sadly the Radeon Drivers just fall over and die and BSOD the Machine with the GPU in Mac EFI mode.

so what I do is I boot into the boot selector, hold control down while clicking the "EFI Boot" Windows disk option this sets windows as the startup disk, while its booting I switch the BIOS switch over to the PC BIOS, let the Machine BSOD and reboot and then (booting blind) since im now running the PC BIOS it will then Boot windows 10 since the AMD drivers can handle a PC (UEFI/BIOS) card just fine with windows booting in EFI mode. (and once im done in windows I switch back to my Mac EFI and reboot the machine holding option and selecting OS X SSD of course)

I hope this helps (and indeed its quite convoluted but its the only way I have been able to EFI boot windows with my AMD Radeon HD 7950)
 

LightBulbFun

macrumors 68030
Nov 17, 2013
2,808
3,125
London UK
Hi!

The answer is, for me, to complicated. I have an inferior education. But if I understand you correct, what I suggested was not correct? So I should leave the switch as it is. To the "right" then.

Thanks for you time and I am sorry for disturbing you!

Best regards

/Per

When I use Sierra High and Hi and thanks for the fast relpljasdf

sorry that I did not awnser your issue clearly

what id recommend in your case is, unless you need/want windows in EFI mode, is Just install windows in "in ordinary old fashion way (non-EFI)" BIOS mode and leave the BIOS switch on the 7950 on the "Mac" side :)

Windows supports UEFI, not Apple's old deprecated EFI.

note that I never said UEFI...

im not saying Apples EFI implamentation is good or bad but I dont think windows has a Specific version or type of UEFI or EFI it explicitly does or does not support, it just requires certain things that not all Mac EFIs implement (for example windows Vista and windows 7 Require a legacy VGA component to display an image during EFI boot which no Mac EFI implements and that every Mac from about 2015 onwards does not even support CSM/Legacy OSs only EFI compatible ones)

I suspect the BSODs going on here is due to buggyness with the EBC Firmware in the 7950 it self and the windows drivers and not the Mac Pro EFI it self. as otherwise the Mac Pro Boot windows 8.1+ in EFI mode just fine,

hell I even managed to boot windows 10 in EFI mode on a 2006 Mac Pro :) (this was done with an Apple ATI Radeon HD 5770)

img_0251-jpg.633077


and a 2006 MacBook2,1 :)

upload_2018-1-31_1-54-7.png


Macs from about 2006 to early 2009 do not fully support some features windows 8.1+ want during EFI booting and as such when you try and boot windows in EFI on those macs you dont get any picture (it just freezes at whatever screen your at say the boot picker or goes blank) but windows does continue to boot and once the GPU drivers kick in everything is fine (because windows is still booting just blind) but macs from Mid 2009 and onwards do support the things needed by Windows 8.1+ and as such you do get a proper picture with the spiny dots and pre GPU driver environment although like the 7950 not all GPU drivers play ball in EFI mode (Iv noticed the MCP79 Macs when you setup the GPU drivers there they tend to just BSOD)

I hope this all makes sense :) Just wanted to mention a few things about Mac EFIs and booting windows in EFI mode on them.
 
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expede

macrumors regular
Original poster
Jan 15, 2018
236
67
Sweden
Thank you LightBulbFun. I leave it on the Mac-side. I do not mean that I am inferior educated. I´m a consultant at the Departement of Oral and Maxillofacial Surgery at a University Hospital, so do have some education. Not as deep in programming as You girls/guys have.

Best regards

/Doc
 
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LightBulbFun

macrumors 68030
Nov 17, 2013
2,808
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London UK
UEFI is a mainstream standard. The fact that you didn't say "UEFI" is of no consequence - Apple does not support the standard UEFI protocols.

Windows (and Linux) support the current UEFI standards. Apple uses an ancient deprecated "EFI" standard, which they've modified in a non-standard way.

It has nothing to do with whether Apple's "EFI" support is good or bad - it's that Apple doesn't support the current industry standard UEFI protocols. Windows and Linux systems that support UEFI have serious issues with Apple's bastardized "EFI" support.

Is this vendor lock in? It looks like it is.

im pretty sure Apple on modern Macs support most of the UEFI standards, its the only way to boot an OS on those models as they depreciated CSM support back in 2015...

also regardless of EFI stuffs, all you do is show up on diffrent threads here bashing apple, im not saying apple is perfect and I dont mind a bit of bashing here and there, but it would be nice if you could actually contribute something to this forum, you sound like you might know a thing or 2. but all you do is just show up and bash.

its your constant bashing/moaning about apple, without contributing anything that irks me the most...

what am I saying this is Mac Rumors! LOL

(its also worth noting that Macs have had EFI since 2006 which is a good couple years before UEFI) and im not even going to go into OpenFirmware :) If you want to see me go into that feel free to check out the PowerPC section of this forum.
 

AlexMaximus

macrumors 65816
Aug 15, 2006
1,181
538
A400M Base
Is this switch the reason it didn't work? Maybe this is a stupid question. I am just a user.

Mac Pro 5.1 (2012), 28GB, Sapphire 7950 White Mac Edition.

Best regards

/Per[/QUOTE]




I had the exact same card as you have, before I switched to the GTX 680 and then to my current 980Ti. I never used the switch in or for bootcamp as well.
I give you one advice on that white Mac Edition card: Sell it on eBay as fast as you can.
Drop that thing like a hot potato and get an Nvidia card. - I mean it - The difference is a whole dimension if you work with GPU bound software that needs NVIDIA and Cuda support. Dimensions..
And it sure doesn't hurt for that occasional Steam game, should you do some of that nature as well.
 

h9826790

macrumors P6
Apr 3, 2014
16,614
8,546
Hong Kong
Is this switch the reason it didn't work? Maybe this is a stupid question. I am just a user.

Mac Pro 5.1 (2012), 28GB, Sapphire 7950 White Mac Edition.

Best regards

/Per

The switch works, that UEFI VBIOS is correctly supported in Windows EFI mode. However, the dilemma is... if you boot from the UEFI VBIOS, you can't see the boot screen, so how to choose "EFI" (in boot manager) to install Windows in EFI mode (or boot from it later on) is already a problem. And if you boot from Mac EFI mode, you can see the boot screen, but Windows crash in EFI mode.
 
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maflynn

macrumors Haswell
May 3, 2009
73,478
43,405
[MOD NOTE]
Some posts were removed as they were derailing the thread. Please stay on topic.
 

lie2me

macrumors member
Apr 23, 2010
93
36
Somewhere
I had the exact same card as you have, before I switched to the GTX 680 and then to my current 980Ti. I never used the switch in or for bootcamp as well.
I give you one advice on that white Mac Edition card: Sell it on eBay as fast as you can.
Drop that thing like a hot potato and get an Nvidia card. - I mean it - The difference is a whole dimension if you work with GPU bound software that needs NVIDIA and Cuda support. Dimensions..
And it sure doesn't hurt for that occasional Steam game, should you do some of that nature as well.[/QUOTE]


Mojave Support? Will the GTX 980Ti work with Mojave on a Mac Pro 2010-2012?
Given the Sapphire HD 7950 seemed to be supported by Apple, I would assume this to be the one card to support Mojave on a Mac Pro 2010-2012.
 

MIKX

macrumors 68000
Dec 16, 2004
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690
Japan
expede ( Per )

I have a 7950 & a 7970 .

I labelled the switch positions (2) left WIN (1) right Mac.

Both my 7950 & 7970 are now EFI flashed with the switch set to ( 2 ) right Mac.

As for Windows I have installed both Win 7 & Win 8,1 on their own spinner HDDs - they both boot OK from the efi boot selection screen. ( Note : They are slow to boot up = black screen with flashing cursor for about a minute .. then they boot.
 
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crjackson2134

macrumors 601
Mar 6, 2013
4,823
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Charlotte, NC
expede ( Per )

I have a 7950 & a 7970 .

I labelled the switch positions (2) left WIN (1) right Mac.

Both my 7950 & 7970 are now EFI flashed with the switch set to ( 2 ) right Mac.

As for Windows I have installed both Win 7 & Win 8,1 on their own spinner HDDs - they both boot OK from the efi boot selection screen. ( Note : The yare slwo to boot up = black screen with flashing cursor for about a minute .. then they boot.

Are you saying you have a 7970 with a firmware switch?
 

MIKX

macrumors 68000
Dec 16, 2004
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The reference HD 7950 3gb cards are great The HIS IceQ versions in particular have the best cooling system I've seen to date - they pump hot air OUT of the case. My HIS is quieter than either of my hd 5770's or two HD 5870's.

The ref HD 7970 cards only take up 1 PCie2 slot

Reference 7950's can be very easily EFI flashed ( Netkas script) plus ( ref cards only ) the 5.0 GT/s mod is dead easy.

IMHO AMD ref. HD 7950 3Gb + bios switch = more than enough for my needs.
 

h9826790

macrumors P6
Apr 3, 2014
16,614
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Hong Kong
The reference HD 7950 3gb cards are great The HIS IceQ versions in particular have the best cooling system I've seen to date - they pump hot air OUT of the case. My HIS is quieter than either of my hd 5770's or two HD 5870's.

The ref HD 7970 cards only take up 1 PCie2 slot

Reference 7950's can be very easily EFI flashed ( Netkas script) plus ( ref cards only ) the 5.0 GT/s mod is dead easy.

IMHO AMD ref. HD 7950 3Gb + bios switch = more than enough for my needs.

No need for any 5GT/s mod anymore now. All we need is just the 138.0.0.0.0 firmware.
[doublepost=1534878674][/doublepost]
Are you saying you have a 7970 with a firmware switch?

Correct, reference 7970 also has ROM switch, it's almost identical to a reference 7950.
 
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crjackson2134

macrumors 601
Mar 6, 2013
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Charlotte, NC
Awesome, Thanks!

Mine actually has the location marked on the PCB but no switch, but exactly the same visually otherwise.

In an unmodified card, what is the switch for? A backup copy of the UEFI ROM?
 
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tsialex

Contributor
Jun 13, 2016
12,955
13,196
Awesome, Thanks!

Mine actually has the location marked on the PCB but no switch.

In an unmodified card, what is the switch for? A backup copy of the UEFI ROM?
Some high end cards, the manufacturer installed a double size SPI-Flash and with the switch you can select the high or low banks of it, effectively creating a backup ROM.

With Mac Edition cards, an EFI or an UEFI ROM.
 
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MIKX

macrumors 68000
Dec 16, 2004
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690
Japan
No need for any 5GT/s mod anymore now. All we need is just the 138.0.0.0.0 firmware.
[doublepost=1534878674][/doublepost]

Correct, reference 7970 also has ROM switch, it's almost identical to a reference 7950.

So does the HIS 7950 and the Sapphire 7970.
 
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