AMD Radeon HD 7950: screen goes black, restart necessary

[zephonic]

I purchased a flashed MSI Radeon HD7950 off Ebay, and stuck it in my 4,1>5,1 (see sys specs below)

It boots just fine, although it bootcamped in 800x600 mode, and I had to manually install the drivers for my Win7Ulti(32-bit) drive.

Everything seems to work okay, but I get random screen dropouts, screen just turns black and only a reboot will do. The longest I've gone so far is 20-30 minutes, but it WILL happen. Is this a known issue? Is there a fix? If not, I think I'm gonna return this. If these screen blackouts keep happening it is of no use to me.

Thanks.

 

[h9826790]

Return the card. To me, it seems like a badly flashed card, or a half failure card. I have both official Mac Edition card and a self flashed card (I do that myself). And I am sure that the 7950 drive in 10.12.6 doesn't has this bug. You issue is very very abnormal.

 

[zephonic]

Returned. At least the seller promptly issues a return label.

Still a bit bummed about this. I was really looking forward to an improved GPU. Not sure I want to pony up $500+ for an official 7950, though...

 

[fendersrule]

Happy with my unflashed R9 7950OC. Zero issues.

If you're on the look-out, you can buy a 7950 for $80 if look in the right places (unflashed). I would never, ever, pay over $150 for one, flashed or not. I don't even think I would want to buy a flashed card to be honest, unmolested is better.

When I was in San Francisco last weekend, a 7970 popped up on craigslist for $80 w/original box (and stated it wasn't used for mining and only the occasional game). They're out there!

 

[zephonic]

Unflashed? No other gpu in your system? And it works fine with Sierra and Bootcamp Windows?

The 'no-bootscreen' thing is an issue for me as I frequently restart to run Windows, and occasionally older iterations of OSX.

 

[h9826790]

Unflashed? No other gpu in your system? And it works fine with Sierra and Bootcamp Windows?

The 'no-bootscreen' thing is an issue for me as I frequently restart to run Windows, and occasionally older iterations of OSX.

You don't need bootscreen at all under normal ops. Quite a few of us (including me now) running a single un-flashed card with multiple OS. All you need to do is just select your next boot drive in system preference before restart. No need to call the boot manager. In fact, select boot drive inside the OS is much faster than waiting boot manager to show up.

 

[MIKX]

You have a BIOS switch on your card. Have you tried the OTHER position yet ? ( power down first ).

Could be a bad flash.

You could SAVE both extant roms. Then re-flash it using the Netkas script - my HIS 7950 works perfectly in Mav, Yosemite, Sierra 10.12.6 & Win 7.

I'm using the bottom DVI to DVI & mDP to DVI = efi boot on both

Here for the Netkas script. http://forum.netkas.org/index.php?PHPSESSID=129t4km0d8luq5nhl252fohv75mkbk93&topic=5619.0

==================================================

You could even bump up it's PCIe link speed to 5.0 GT/s

Post #199
https://forums.macrumors.com/thread...-and-nvidia-card.1547340/page-8#post-24856990

 

[zephonic]

You don't need bootscreen at all under normal ops. Quite a few of us (including me now) running a single un-flashed card with multiple OS. All you need to do is just select your next boot drive in system preference before restart. No need to call the boot manager. In fact, select boot drive inside the OS is much faster than waiting boot manager to show up.

And if you come from power down?

 

[h9826790]

And if you come from power down?

If you mean you want select OS in a cold boot. You can do it blindly. The boot manager is there, but just you can't see it.

Of course, this is not a good way to use it. And in fact, the OS boot so fast now with SSD. It only cost you few more seconds if you let it boot to desktop and then select OS + reboot.

If for any reason you want to avoid boot to desktop, but must go into another OS before boot to the default OS. The you can boot to recovery partition, and choose next boot drive at there.

Also, in any case, a PRAM reset will make the system default boot to MacOS.

I have 2 EFI cards, but they are both in the box now. I am currently running a R9 380 which can't be flashed. And I have 2 MacOS + 1 Window 10 partitions. And I occasionally use another 2 Linux LiveCD as well. Totally 5 different OS, not need boot screen at all.

All hot key still works without boot screen. e.g. command + R can boot to recovery partition, holding C can boot form the disc etc. If boot screen available, of course use it. But that's really no big deal if you can't have that (even running multiple OS).

But I also suggest you get a cheap 7950 and flash the card by yourself. As MIKX pointed out, 7950 should come with dual ROM, that make the flash process fail safe. And you can have one ROM flashed with EFI, and the other one keep it un-mod. No need to pay for an expensive 7950.

If you really want to use that OWC price to buy the Sapphire 7950, please let me know. I sell mine to you with 20% off (it's a real Sapphire 7850 Mac Edition, not the flashed card), and I can give you low power mod, high perform mod, low fan noise mod, high performance thermal paste mod, etc. with no extra charge, haha

Also, there is a little bug in MacOS which only affect the 7950 Mac Edition card (flash card actually not affected). Which is the screen may shutter occasionally in desktop environment (if you only connect one monitor to this card). If you buy my card, I can fix that for you for free as well

Anyway, I think it is much more reasonable to pay ~ $100 to get the virtually identical and bug free card, but not $500+ for this old card.

 

[fendersrule]

Yep. Boot screens are overrated! I was so worried about not having boot screens that I was considering paying $300+ for an old ass card (which the 7950 and the 680 is). Don't do it!

I had to disable SIP to be able to boot to and fro from either OS. It was super painless to do. Now, it's actually much faster to simply use the "Boot in Mac OS" or "Boot in Windows" instead of holding down the alt key....it's way faster!

h98 is right. If you need a hard restart to recover, by default, the machine will boot into Mac OS. Takes about 15-20 seconds, which is nothing. Then you simply just restart back into Windows from there. Honestly, I had to do this like 2-3 times in the past 4 months. So it's hardly a worry or an issue!

Btw, I've never been successful at "blind" booting with the manager. I almost feel like a black screen also means = nothing behind it. I may be incorrect, but I tend to remember spending 10 minutes on trying to do things blindly and got zero system response from it...

To be honest, I don't even consciously think that I have an unflashed card during use. That's how fast and smooth it is...

Another thing, the 7950 is bugged if you have an EFI installation of Windows. You should try to shoot to have Windows 10 installed via EFI mode. Super fast....faster than Mac OS Sierra in every way. Boots faster, more responsive, etc. Bios, I cannot say, but I am so impressed with EFI Windows that I wouldn't change it for anything...and flashed 7950's (or even the real Mac Rom) doesn't play nicely with it. An unflashed 7950 plays nicely with everything, so there's reasons to not flash a 7950 if you want the best installation of Windows 10 possible (EFI).

Don't overpay for old stuff! A 7950 is a superior card to the 680 due to having 3GB of VRAM (which is super important to have for modern games), but it's not necessarily something I would say is a "hot-rod" of a gaming card in 2017. With a mild overclock in Windows 10, it actually performs nicely in 1440p in all the games I play, (TF2, Metal Gear Phantom Pain, Vermintide, Killing Floor, ANY Indie game, etc). But running a modern triple A title at 1440p maxed out I would not expect the 7950 to do with ease.

7950 is a great card. It's a super great card for $80, but paying over $150 for one, even upwards of $300 is super nutty. And a flashed 7950 is a non-starter for Windows EFI mode (no worky), so IMO, an unflashed 7950 makes for a damned good, cost effective, 5,1 card.

 

[zephonic]

No, I wasn't gonna go get a 7950 Mac Edition for >$500. An insane price for a 6-year old GPU, but that's Apple aftermarket stuff for you.

I did consider this one: http://www.ebay.com/itm/NEW-Radeon-...228335?hash=item3aea6eba2f:g:eCgAAOSwEUVZZZjr

But if an unflashed card does indeed works fine and costs less than $150, I may have to consider that. However, the truth is, I don't really need it for work. I'm a music/audio dude and the GT120 suffices for all of that. I just thought that a GPU upgrade would be a logical next step after I did the 4,1>5,1 hex thing earlier this year. I'd really like to be able to play Cities:Skylines, but it's not a must.

Thanks all for chiming in.

 

[fendersrule]

Yea, $275 is still too expensive for a 280/7950. Get a used one for $80 and you'll be super happy.

 

[Squuiid]

Or a GTX 680, or even better wait for availability of a Sapphire RX 580 Pulse 8GB.