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NVIDIA GeForce GTX 980 Ti
- Thread starter vanlam
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Oh yeah for compute it's a different story because you are earning money from those compute units
drivers were updated, Cuda too. I keep swapping them out. Reboot and it works good for undetermined amount of time then just kind of flakes out. Cursor gets all slow and notch. Swapped out the 680 and I notice that does it too but takes longer. Something is up. Memory seems to be used up as artifacts start to appear on the screen, which is hard to believe on a 6GB card. Seems to flake out faster with a browser window open. No browser open and I can get some good work out of it. Baffling. Currently testing to see if the internal temperature has something to do with it....which seems to show some promise. will keep you posted.
So after installing iStat Menus I watched the internal temp....when things got to about 95º ambient the card started acting weird. Turned the fans on and let it cool down to 85º and things seem to be much better. Twitch every now and then but no artifacts or permanent slow down. Will do some rearranging tomorrow and move the 980 to 2nd slot for better cooling. Seems like it's very sensitive to temperature in this tower.
Are you running a custom fan set up via iStat? Maybe the card is drawing too much power and causing the heat up? Would be interested if you get to the bottom of it as I’m close to buying a 980Ti for my Mac Pro tower and I’m going to have to put it into slots 0+1. Slot 2 holds my x2 SSD boot drive, slot 3 will eventually hold my GT120 for a boot screen and slot 4 my SM951 media drive. Can’t really move them.
So here is what I found out. It all appears to be heat related. That would explain why it works for a bit and then flakes out after a few minutes. Did some searching and good answer turned up over at the World of Warcraft forum:http://us.battle.net/wow/en/forum/topic/15699631352
It appears that the 9XX series has an openCL bug that when the card is called it goes to full clock speed and doesn't slow down until a reboot. This wouldn't be a problem if you just used it for gaming, but now that Creative Cloud 2015 has GPU acceleration, it calls on openCL quite often. I installed iStat monitor and when the ambient temperature rises to 95º it starts getting video artifacts and jerky mouse. I turned on a custom fan control and once it cooled down it came back to normal. I installed Mac Fan Control and set a custom fan setting to kick in when the ambient temp rises above 88. I also moved the video card to slot 2 and my SSD to slot one to create more air flow around it. Probably not necessary, but every bit helps. With this setup it has been very useable. Hopefully Nvidia addresses this bug as they continue to develop drivers.
It appears that the 9XX series has an openCL bug that when the card is called it goes to full clock speed and doesn't slow down until a reboot. This wouldn't be a problem if you just used it for gaming, but now that Creative Cloud 2015 has GPU acceleration, it calls on openCL quite often. I installed iStat monitor and when the ambient temperature rises to 95º it starts getting video artifacts and jerky mouse. I turned on a custom fan control and once it cooled down it came back to normal. I installed Mac Fan Control and set a custom fan setting to kick in when the ambient temp rises above 88. I also moved the video card to slot 2 and my SSD to slot one to create more air flow around it. Probably not necessary, but every bit helps. With this setup it has been very useable. Hopefully Nvidia addresses this bug as they continue to develop drivers.
Thanks for delving into the problem, good insight. Also, good that it’s a fixable bug and that you can instigate a temp fix with fan control. Have you got a flashed version of the Ti from MacVidCards or are you using a stock card without a boot screen?
You can force the GPU to return to resting state by starting Cuda Z, go to the performance tab and then quiting the app
I am using a PC EVGA card with their 2.0 cooler. It is not flashed. Boot screen is black, but have no trouble with that. SSD boots so fast you barely notice it is gone.
I have not seen this problem with my 980Ti... I have the EVGA reference board that is factory overclocked...
I don't see temps increase out of control after running benchmarks like Valley or Haven for an extended period of time... If anything the only concern I have is the fans seem to stay slower by compared to when I had the 660TI and pulled all power off the logic board. I added a dedicated 8pin connection straight from the PSU and powering just one 6pin off the logic board...
I don't see temps increase out of control after running benchmarks like Valley or Haven for an extended period of time... If anything the only concern I have is the fans seem to stay slower by compared to when I had the 660TI and pulled all power off the logic board. I added a dedicated 8pin connection straight from the PSU and powering just one 6pin off the logic board...
Also, how did you do this? I assume soldering onto the PSU was involved?
I've read about people running from a separate PSU or just from the internal PSU, but not from both as you appear to be doing.
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And can I ask, with your card being unflashed, does it only connect at PCIe 1.0 speeds, not PCIe 2.0?
Yes, I was inspired by several here who have done the same. Check out this thread: https://forums.macrumors.com/threads/pixlas-4-1-mac-pro-mod.1859652/unread
It is not something you should tackle if you are not experienced with soldering though... I ran a heavy enough of a line, that I planed for two 8-pin connections so I can add another 980Ti and SLI in Windows down the road if I need a little more head room in games...
Think that might not be the case if you run the Nvidia Web Drivers, which you need to do to run this card... But yes, as you said the difference is not as dramatic as you might think...
Updates to PCIE specification were to primarily address servers with a lot of network traffic that are using enterprise SSDs on the PCIE slots. For gaming it makes such a small difference.
And I assume it makes an equally small difference for graphics and 3d work too?
I did read a post somewhere on here about the 1.0 & 2.0 difference and how it was largely meaningless speedwise. I'll try and find it and post a link here.
Almost no difference. Once all the geometry and textures are loaded into the video memory there is very little data going across the system bus. Most of that data the files are much smaller than the PCIE bandwidth.
Here's a link showing a summarised set of benchmarks between PCIe speeds 1.1, 2 .0 and 3.0. At the most it's a 4% increase at 2.0 over 1.1, at the least its 2% (comparing the x16 slot results). Testing was done using various games. Would be interested to see various 3D app benchmarks summarised in the same way but I'm guessing it would be much the same result.
http://www.techpowerup.com/mobile/reviews/NVIDIA/GTX_980_PCI-Express_Scaling/21.html
http://www.techpowerup.com/mobile/reviews/NVIDIA/GTX_980_PCI-Express_Scaling/21.html
I’m using the GTX 980 Ti (Gigabyte G1 Gaming) for about 3 weeks with my old Mac Pro 5.1 now, it replaced a R9 280X OC.
As the fans aren’t needed under 60 degrees they stand still most of the time while doing normal „office stuff“ or „simple photo retouching“ with Photoshop.
But to be honest I’m currently using this Mac + 980 Ti for gaming @ 4K with Windows 10 which is why I haven’t really tested working with my Adobe CC Apps or Capture One on OS X.
With OS X ( 10.10.3 + NVIDIA Web Drivers) both GTX 980 Ti and the old GT 120, which I use to get a bootscreen, are recognized and seem to be working fine.
On Windows 10 the drivers for the old GT 120 (listed as GT 9500) aren’t included within the new drivers for the 980 Ti which is why additional drivers are installed - the result is an „error 43“ and the GTX 980 Ti is disabled…
I’m still looking for a (software, drivers, Windows) solution but apart from this I’m quite happy with the performance of the 980 Ti on Windows 10 - the fps @ 4K with games like „Witcher 3“ are great.
While playing the GPU load is of course quite high, I only use the internal power of this old Mac.
In order not to destroy the Mac I’m not only using the standard 2 x 6-pin PCIe power cables of the system board but also 4 x SATA-Power.
Up to now this works fine.
As the fans aren’t needed under 60 degrees they stand still most of the time while doing normal „office stuff“ or „simple photo retouching“ with Photoshop.
But to be honest I’m currently using this Mac + 980 Ti for gaming @ 4K with Windows 10 which is why I haven’t really tested working with my Adobe CC Apps or Capture One on OS X.
With OS X ( 10.10.3 + NVIDIA Web Drivers) both GTX 980 Ti and the old GT 120, which I use to get a bootscreen, are recognized and seem to be working fine.
On Windows 10 the drivers for the old GT 120 (listed as GT 9500) aren’t included within the new drivers for the 980 Ti which is why additional drivers are installed - the result is an „error 43“ and the GTX 980 Ti is disabled…
I’m still looking for a (software, drivers, Windows) solution but apart from this I’m quite happy with the performance of the 980 Ti on Windows 10 - the fps @ 4K with games like „Witcher 3“ are great.
While playing the GPU load is of course quite high, I only use the internal power of this old Mac.
In order not to destroy the Mac I’m not only using the standard 2 x 6-pin PCIe power cables of the system board but also 4 x SATA-Power.
Up to now this works fine.
Don't allow Windows Update to ever install any Nvidia driver otherwise it enables the GT120 and disables the newer cards. If this happens:
-uninstall any Driver software
- delete both cards from device manager
- reboot
-When it reboots the GT120 will be installed as a generic Windows card. Never allow Windows Update to install any video driver
- install the latest GeForce driver direct from Nvidia to enable the newer card
I ran into that after first getting my 980Ti, figured that out the hard way... Also can't launch the Nvidia control panel unless you then disable the GT120...
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Hello Xactoman,
Thanks for sharing, I have received my ZOTAC GTX 980 Ti and have been playing around with it for couple of days now. I did a fresh Yosemite install on a spare SSD with a flashed 280X and then installed the latest Nvidia web drivers and replaced the card with GTX 980 Ti, just to test.
I use my cMP (Home machine) for photo editing, Adobe CC, CAD and some video editing on FCPX. I can confirm that for some reasons it will be very laggy, I can hardly open or close safari and cannot navigate through the finder. Mine is clocked at 1000 MHz and boost at 1076 MHz (no GPU overclocking).
If I up-ed my case fans, it does help. However, it still feels like the UI is struggling with the compute power of the GPU. Sometimes it feels very fluid and snappy, and sometimes it will slow down. I think it is related to the bug you mentioned. I hope that Nvidia/Apple release new drivers.
The hack of adding NVIDIA card to CC does not seem to work with GTX 980 Ti on OSX, need some more testing. FCPX is ok, but rendering time has increased a little bit. I am not sure why, GTX 980 Ti scored better than R9 280X on Luxmark. Other apps work well when the bug is not consuming the GPU resources. Any other fix I should try?