PCIe Link Speed Issue

Alex Sanders74

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Did a search on this and was unable to find any related posts... Having an issue with a GTX750ti linking at 16x 5GT in Slot 1. I realize this was an issue with older Boot ROMs and cosmetic. Running High Sierra with 141.0.0.0 Boot ROM and the card is linking at 8x 2.5GT still. Some screenshot attached with details. Cl!ng is showing low scores as well. Performing the same as the High Sierra ROM was showing.

Card is a Gigabyte Windforce GTX750ti, PC EFI and works perfectly, sans bootscreens. Seems like it's underperforming. Any thoughts you all may have would be appreciated.

Edit: Running 387.10.10.15.15.108 web driver and the latest CUDA driver 410.130

Screen Shot 2019-02-05 at 10.33.27 PM.png
Screen Shot 2019-02-07 at 11.04.13 PM.png
Screen Shot 2019-02-07 at 11.13.20 PM.png
 
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bsbeamer

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Sep 19, 2012
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Assume this is a non-EFI (not modified) GTX 750 Ti?
How is it being powered?

Did you have this same issue with 140.0.0.0.0 firmware, or was this new with the 141.0.0.0.0 beta firmware?
 
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startergo

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Sep 20, 2018
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Thanks for the feedback. I'll try both those options. Odd thing is the original Radeon 5770 is linking at 16x and running at the full 5GT....
I got the same thing 5770 or gt-120 was at 5GT. I am not sure what fixed it ultimately though I found some bent pins on the CPU tray connector which I fixed . Re-seating the card might have helped too .
 

bsbeamer

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Did you reset PRAM when installing/swapping GPUs, or is the BR2032 battery dead (which effectively could reset PRAM when power cable is removed)?
 

Alex Sanders74

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Original poster
Nov 26, 2013
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Toronto, Canada
Assume this is a non-EFI (not modified) GTX 750 Ti?
How is it being powered?

Did you have this same issue with 140.0.0.0.0 firmware, or was this new with the 141.0.0.0.0 beta firmware?
Previous firmware was the 089 High Sierra, which was flashed to 141.0.0.0.0 with tsialex's help, so i Know that's not an issue. Firmware is clean and was done a couple days ago.

Didn't zap PRAM, but is this a good idea considering the firmware was a completely clean flash from a rebuild clean firmware? Are there any drawbacks to PRAM flash when running Nvidia web drivers?

Card is non Mac ROM powered with single 6 pin from the board. Been running it this way since day 1.

Have a brand new battery. I changed it when I got the tower a couple weeks ago.

Appreciate your feedback.

[doublepost=1549639461][/doublepost]
I got the same thing 5770 or gt-120 was at 5GT. I am not sure what fixed it ultimately though I found some bent pins on the CPU tray connector which I fixed . Re-seating the card might have helped too .
I'll look at the tray. I removed it to blow out the massive amount of dust that had accumulated. Was very cautious when removing it and replacing but it's a possibility. Thanks for the suggestion.
 

bsbeamer

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Sep 19, 2012
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I am not positive about the 141.0.0.0.0 firmware since it is in beta and not officially released publicly at this time. If 5770 and 120 are showing x16 and 5GT/s it may answer the question if this is a specific issue about the 141 firmware vs 140 firmware. MOST people right now are on the 140 firmware and you will have a hard time getting firm 141 reports for the next few weeks.

PRAM reset may be necessary and has cleared reporting issues with 138 and 140 firmware for many users in the past. Believe your GPU is a natively compatible GPU and does not 100% require NVIDIA driver for operation. You also appear to have EFI GPUs on hand IF there are any issues.
 
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Alex Sanders74

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At work for a while right now but I'll give all the suggestions a try when I get home. PRAM reset will be first on the list. Definitely will report back regardless of what the outcome is.
 

tsialex

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I am not positive about the 141.0.0.0.0 firmware since it is in beta and not officially released publicly at this time. If 5770 and 120 are showing x16 and 5GT/s it may answer the question if this is a specific issue about the 141 firmware vs 140 firmware. MOST people right now are on the 140 firmware and you will have a hard time getting firm 141 reports for the next few weeks.

PRAM reset may be necessary and has cleared reporting issues with 138 and 140 firmware for many users in the past. Believe your GPU is a natively compatible GPU and does not 100% require NVIDIA driver for operation. You also appear to have EFI GPUs on hand IF there are any issues.
This problem is unrelated to NVRAM or PRAM issues.

  1. MP5,1 don't have PRAM, last Mac Pro that have some sort of PRAM is MP3,1 and it's nothing like an Open Firmware PRAM.
  2. @Alex Sanders74 reconstructed BootROM, and any that I reconstructed, has a totally clean NVRAM. Once flashed, the NVRAM is overwritten by an empty one and there is no need to clear NVRAM again.
Btw, GTX 750Ti is a Kepler card and has Apple native Nvidia drivers support. You can clear NVRAM anytime with a Kepler card, just go to the Nvidia applet into System Preferences and activate the web drivers again.
 

Alex Sanders74

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Thanks good sir for your feedback.

Seems it might be a tray pin then or bad card seating? It's registered at this speed since I initially got it and the 5770 I have works at full speed every time. Frustrating to say the least... I've swapped it out for the 5770 a few times over the last week or so and the result is always the same. Maybe try it in Slot2? I have no other PCIe cards right now.
 

tsialex

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Thanks good sir for your feedback.

Seems it might be a tray pin then or bad card seating? It's registered at this speed since I initially got it and the 5770 I have works at full speed every time. Frustrating to say the least... I've swapped it out for the 5770 a few times over the last week or so and the result is always the same. Maybe try it in Slot2? I have no other PCIe cards right now.
You should try to install into slot-2 before anything else, for sure, but could be a defective GPU.

I have a GT120 that only works at 2.5GT/s, later I found that a SMD resistor is missing from the backside of GPU board. It's on my pile of things to repair for sometime.
 

Alex Sanders74

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Will try the slot swap and also have a second 5.1 I can try it in as well.. Might rule out the tray issue without messing about too much. Never gave the BootROM any consideration as it was as clean as it could ever be. Thank you again for your help with that.

If the GPU is defective, I'm not too concerned. It was very inexpensive and am looking at a GTX980 to replace it.

Will try this later today and post results. Thanks to all for your valuable feedback.
 

startergo

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Sep 20, 2018
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Will try the slot swap and also have a second 5.1 I can try it in as well.. Might rule out the tray issue without messing about too much. Never gave the BootROM any consideration as it was as clean as it could ever be. Thank you again for your help with that.

If the GPU is defective, I'm not too concerned. It was very inexpensive and am looking at a GTX980 to replace it.

Will try this later today and post results. Thanks to all for your valuable feedback.
FYI When I had the issue it worked in the second slot at 5GT same as the others . It only had a problem in Slot 1. And only the RX 580
 
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tsialex

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Will try the slot swap and also have a second 5.1 I can try it in as well.. Might rule out the tray issue without messing about too much. Never gave the BootROM any consideration as it was as clean as it could ever be. Thank you again for your help with that.

If the GPU is defective, I'm not too concerned. It was very inexpensive and am looking at a GTX980 to replace it.

Will try this later today and post results. Thanks to all for your valuable feedback.
Since you have access to two more Mac Pros, check the GPU behaviour when installed into another one. This will easily show if the problem is the GPU or your suspected Mac Pro.
 

bsbeamer

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Sep 19, 2012
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Please also report what firmware version those other Mac Pro's are using. Do not believe this is related to 141.0.0.0.0 firmware at all, but worth double-checking on your setups.
 
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Alex Sanders74

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Nov 26, 2013
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Thanks guys.. I'm curious about the 141 firmware as well, but maybe someone else is running an Nvidia card with this version of firmware and can chime in if it's linking correctly.

Other Pros I have will be running Pre Mojave firmwares, so link speeds will likely show at the reduced rate, but Cl!ing may tell otherwise. I know the speed problem was cosmetic in Pre Mojave versions.
 

tsialex

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Thanks guys.. I'm curious about the 141 firmware as well, but maybe someone else is running an Nvidia card with this version of firmware and can chime in if it's linking correctly.

Other Pros I have will be running Pre Mojave firmwares, so link speeds will likely show at the reduced rate, but Cl!ing may tell otherwise. I know the speed problem was cosmetic in Pre Mojave versions.
I've sent you 140.0.0.0.0 via PM. I doubt that will change anything, but let's confirm.
 

Nabru50

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Aug 24, 2017
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This problem is unrelated to NVRAM or PRAM issues.

  1. MP5,1 don't have PRAM, last Mac Pro that have some sort of PRAM is MP3,1 and it's nothing like an Open Firmware PRAM.
  2. @Alex Sanders74 reconstructed BootROM, and any that I reconstructed, has a totally clean NVRAM. Once flashed, the NVRAM is overwritten by an empty one and there is no need to clear NVRAM again.
Btw, GTX 750Ti is a Kepler card and has Apple native Nvidia drivers support. You can clear NVRAM anytime with a Kepler card, just go to the Nvidia applet into System Preferences and activate the web drivers again.
I also have a Mac Pro 4,1 > 5,1 with a 750Ti by EVGA, and I can almost swear I could not get it to display anything without installing the nVidia web drivers. Are some 750Ti's not kepler?

Looks like I am still on bootrom 140.0.0.0.0, here is my PCIe info.

 
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Alex Sanders74

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Nov 26, 2013
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Screen Shot 2019-02-09 at 12.11.46 AM.png
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Screen Shot 2019-02-09 at 12.26.35 AM.png
I also have a Mac Pro 4,1 > 5,1 with a 750Ti by EVGA, and I can almost swear I could not get it to display anything without installing the nVidia web drivers. Are some 750Ti's not kepler?

Looks like I am still on bootrom 140.0.0.0.0, here is my PCIe info.

Weird. Yours is getting the full 16x speed but only running at 2.5GT. Maybe these cards are just unusual in that regard.

I’m getting 8x and 2.5GT. Both slots 1 and 2 now with 141.0.0.0.0 firmware.

Yep, results are the same in slot 1 and 2. Any ideas wizards of Mac Pro forums?
[doublepost=1549690486][/doublepost]Update: Installed the card in Slot 2 and these are the results... Same ol same ol. What the hell?

Screen Shot 2019-02-09 at 12.11.21 AM.png
Screen Shot 2019-02-09 at 12.11.46 AM.png
Screen Shot 2019-02-09 at 12.12.39 AM.png

[doublepost=1549690689][/doublepost]Installed in the second 5.1 I have with an ancient bootROM MP51.007F.B03.... Exact same result, even with testing with Cl!ng... Realize that system speeds are cometic with this bootROM, but I think this card has an issue.

View attachment 820696
Screen Shot 2019-02-09 at 12.26.35 AM.png
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flowrider

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Nov 23, 2012
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Have you folks tried CUDA-Z?

TinyGrab Screen Shot 2-8-19, 10.57.01 PM.png


My results with CLng:

TinyGrab Screen Shot 2-8-19, 10.57.14 PM.png


They are quite different. BTW, I'm showing:

TinyGrab Screen Shot 2-8-19, 11.00.30 PM.png


Lou
 

Alex Sanders74

macrumors 6502
Original poster
Nov 26, 2013
272
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Toronto, Canada
Have you folks tried CUDA-Z?

View attachment 820701

My results with CLng:

View attachment 820702

They are quite different. BTW, I'm showing:

View attachment 820703

Lou
Weird. Yours is linking at 16x and 2.5GT. I'm still only linking at 8x and 2.5GT. Thanks for sharing that with me. What bootROM are you running on yours? Also, your Cl!ing test seems to show the score for your CPU not the GPU under OpenCL. Going to try Cuda-Z now. Appreciate your feedback.
[doublepost=1549695425][/doublepost]I tried Cuda-Z... this card is beyond salvation in my opinion. Yours is linking at 2 to 3x the speed.

Screen Shot 2019-02-09 at 1.55.15 AM.png