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pyxelfish

macrumors newbie
Original poster
Apr 26, 2008
11
2

I have a Mac Pro 5,1 (late 2009) which was sold to me with a Windows model NVidia GeForce EVGA GTX 680 4GB FTW graphics card. I don't know what most of those acronyms mean, but I was told it had been custom-flashed to work with Mac OS X, and so gave more power and VRAM for the price. The machine came with Mavericks but I rolled back to Mountain Lion, because I use software that did not yet support Mavericks at the time.

The card works very well under Mountain Lion 10.8.5, but I have encountered problems now that I've been wanting to move to Yosemite.

The card has two DVI outputs, one DVI-I and one DVI-D. I have two displays, a HD one with DVI support, and a smaller old one which only supports VGA. I have a VGA adapter plugged into the card's DVI-I port supporting my smaller display, and the primary display is plugged directly into the DVI-D port.

Under 10.8.5 this works fine, but when I have tried booting into 10.9 Mavericks or 10.10 Yosemite (from internal or external disks), the primary display will initially show the boot screen, and then it just shows digital garbage. The smaller display on the upper DVI-I port will still work fine, which allows me to boot into the OS and install the NVidia web driver for the card, but that makes no difference, even after rebooting. Plugging the primary display into the DVI-I port enables it to work, so it's not a problem with the display itself, but then I'm without my secondary display, and it's a massive pain to get into the back of the computer and switch the cables around every time I want to use an app that only supports 10.9+.

I can only surmise that the flashed firmware on the card needs updating, but I know nothing about this and wouldn't know where to start. The seller is unavailable, and successive Google expeditions have produced no useful results, except to point to vaguely related threads on this site and Hackintosh sites. I have also tried running Yosemite under Parallels Desktop (which would be preferable as I've no real desire to change my operating system, except that newer software demands it), but I can't get it to boot – an unrelated issue.

If anyone has any advice I would be very grateful!
 
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There are three 4GB ROM files that can be flashed to a 4GB GTX680 to give it a Mac EFI.

The first one was "found" by Dr. Stealth and is by far the most common one publically available; I believe this is what you have. That ROM originally worked fine, but a MacOS update broke compatibility with the upper DVI port. This appears to be the problem you are having, and it fits that when you downgrade the OS, both DVI ports work again.

The second and third ROMs both work with both DVI ports even on newer versions of MacOS, so the fix will be to go to one of those.

The second one is not available publicly. It was created by MacVidCards and is available by his paid flashing service here.

The third one was created by Florian. If you want to do this yourself for free, you need to download his ROM and flash your card with it. His ROM is here. If you have access to a Windows computer, or you have Windows on your Mac Pro, flashing the GTX680 is quite easy. This is what I would do.

Alternatively, you can connect your VGA monitor to the DisplayPort connector on your video card using an active adapter. This is cheaper than MVC's flashing service, and might be easier than flashing your card (depending on your comfort level with that procedure). This adapter should work. Of course it won't fix your second DVI port, but you'll be able to use the VGA monitor.
 
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ActionableMango, thanks for your quick response!

Since I don't live in the US and don't have the budget to ship my card there for flashing, I'll have to flash it myself. I've never done this before and have no idea where to start. Can you point me towards some reliable instructions?

I've so far been unable to install Windows via Boot Camp on my Mac Pro (I can't remember what snag I hit), but I have been able to get Windows 8 running under Parallels Desktop - although I've not yet attempted to use it. Will this be sufficient?
 
No, a virtual machine won't work. You need Windows booted natively on your Mac Pro or a PC.

Instructions:

Prerequisites:
  • A reasonably normal GTX 680 (the overwhelming majority of them work, but a couple of weird ones don't)
  • A copy of the 2GB ROM or the 4GB ROM file, to match your card's VRAM capacity
  • A copy of nvflash software
  • Windows
Flashing Procedure:

1) Make sure there are no other Nvidia cards installed at the same time.

2) Copy all the related files to a single folder that is easily accessible from the command prompt. I suggest you make a new folder, for example C:\scrappy. It should include the following:
nvflash.exe
GTX680-4GB-ROM.rom
(file name may vary)

3) Open a command line prompt. (Click Start button, type CMD, and press Enter. A command line window will open.)

4) In the command line window, navigate to the folder with the files. If you used my example, the command would be:
Code:
cd c:\scrappy

5) Make a backup of the existing firmware in case you need to go back to it:
Code:
nvflash --save backup.rom

6) Flash the new firmware:
Code:
nvflash -4 -5 -6 GTX680-4GB-ROM.rom

7) If it asks for confirmation, press yes. When it says to wait, wait.

8) After it is successful, reboot and you will see boot screens.

9) Celebrate.
 
Hi ActionableMango.

Thanks for your excellent instructions! They were detailed and pitched at just the right level for someone like me who is proficient in tinkering with Mac OS X, but less familiar with Windows.

I've successfully installed Windows via Boot Camp. Windows 7 still only boots with the secondary screen, like Mac OS 10.9+, but I have installed nvflash and downloaded the rom you linked to.

However I've hit a snag. The command
Code:
nvflash --save backup.rom
seemed to work as intended, but the command
Code:
nvflash -4 -5 -6 GTX680-4GB-DVI.rom
just opened nvflash, with the help page that shows up when you just open the program without giving it a command. I was definitely cd'd into the right folder, and the rom's name was correct.

I've tried googling the issue, but I just found the same instructions you gave me. Any further recommendations?

Thanks so much for your help so far!
 
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note this is an issue I had make sure to download the version 5.134 flasher for windows the latest version doesn't work right and you will never flash the card with it! good luck
 
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I've tried googling the issue, but I just found the same instructions you gave me. Any further recommendations?

CapnDavey's advice is correct. Recent versions of NVFlash seem to have broken compatibility. Try the version he recommends.

It's easier to follow the instructions in the specific 4GB GTX680 thread as that uses the Windows application Kepler BIOS Tweaker rather than the command line nvflash (it actually uses nvflash to do the flash but has a GUI for operation).
https://forums.macrumors.com/thread...ens-full-clock-rates-pci-e-2-0-5gt-s.1603260/

Did that work for you? Many people in that thread including myself couldn't get Kepler BIOS Tweaker to work because it wouldn't flash a mismatched ROM onto the card. The "-4" part of the NVFlash command line overrides the mismatch, but I couldn't figure out how to pass that parameter through the Kepler BIOS Tweaker GUI.
 
CapnDavey's advice is correct. Recent versions of NVFlash seem to have broken compatibility. Try the version he recommends.



Did that work for you? Many people in that thread including myself couldn't get Kepler BIOS Tweaker to work because it wouldn't flash a mismatched ROM onto the card. The "-4" part of the NVFlash command line overrides the mismatch, but I couldn't figure out how to pass that parameter through the Kepler BIOS Tweaker GUI.
Kepler BIOS Tweaker worked for me so that's why I recommended using it. I have previously used just command line nvflash but Kepler BIOS Tweaker makes it a little easier. I have successfully flashed both a 2GB & a 4GB eVGA GTX680 with Kepler BIOS Tweaker.
 
Good news guys! Once I actually managed to get Windows to install the latest Nvidia driver for the card, it seemed to fix the problem – for both Windows and Yosemite. I haven't actually logged into Yosemite yet to play with it but the installer used my DVI display as the main screen.

So in summary, no BIOS tweaker or flashing utility needed, only:
  1. An installation of Windows on an internal drive, and
  2. the latest Nvidia driver for the graphics card.
The driver installer did say "some flashing may occur" in the notes, so I assume that's what's happened. I don't know why the same thing didn't happen under Yosemite – perhaps because it's not a natively Mac-compatible card. Seems silly really, I don't see why there should be a separate, slightly different but more expensive version of the card for Macs.

Thanks everyone for all your help and advice! This has solved a frustrating ongoing problem for me, so I'm very grateful. :) On a related note, does anyone have any recommendations for how to expand the Windows partition now I have one? The partition is at the end of the drive; I've shrunk the Mac partition to create more space for it, but Disk Utility and the Windows partition manager will only expand the partition forwards. Another seemingly pointless restriction... ;)
 
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Cool flashing video cards isn't rocket science but I know its a scary thing for some people so I guess you didn't flash it? it will work un flashed once you feel comfortable doing it you will!
 
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Cool flashing video cards isn't rocket science but I know its a scary thing for some people so I guess you didn't flash it? it will work un flashed once you feel comfortable doing it you will!
Guess what CapnDavey? You were right! I didn't flash the card, and the above process did not work with Yosemite. It appeared to – it worked with the installer, and with Mavericks, but not under Mac OS X 10.10 proper.

However, I have ended up successfully flashing the card for Yosemite as per your advice. For others who find this thread, here is the process I followed, quoted from the source (I have attached all the necessary files below):

Okay..... All the standard disclaimers apply. Don't cry to me if anything goes wrong. :D

1. Download- nvflash_windows_5.134.0.1 - Kepler BIOS Tweaker v1.25 - GTX680-4GB-ROM - Links above.

2. Unzip contents of Nvflash to folder.

3. Unzip GTX680-4GB-ROM and put it in the same folder.

4. Unzip Kepler BIOS Tweaker and put it in the same folder.
rom1.png


*************** Important ! SAVE your Original BIOS file ! ***********************************
5. Start Kepler BIOS Tweaker and use "ReadBIOS" button to read the PC rom image from your card!

6. Click "Save BIOS As" button to save your Original PC rom image to your computer!
***************************************************************************************
7. Use "Open BIOS" button to open the Mac rom image. GTX680-4GB-ROM.rom
rom2.png


8. Now press the "FlashBIOS" button. A command prompt window (nvflash) will open and flash your rom. If it asks you to continue click Y. Wait for it to finish ! Takes maybe 30 seconds.

11. You're finished, re-boot to OS X or Windows to verify all is well.
Thank you all again for your help and advice!
 

Attachments

  • nvflash_windows_5.134.0.1.zip
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  • Kepler BIOS Tweaker v1.25.zip
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  • GTX680-4GB-ROM.zip
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