Ben Trahair

macrumors newbie
Original poster
Dec 8, 2019
3
0
Hi there,

I have a flashed Macvidcards Titan X in my 2010 Mac Pro 5.1.
Since installing the Titan about 4 years ago I've only ever been able to get my machine to boot while using the DVI cable connected to an old monitor the grey apple logo appears after some Commandline text- once it reaches the login screen I can then plug in a second display via mini display port and it picks up the DisplayPort signal and I can disconnect the old DVI monitor.

This is great except that it means I can't restart or shutdown my machine very easily.

When I do start up with the Titan connected to a more modern display (I've used a BenQ 4k pd2700u and also an old iMac) via DisplayPort or HDMI it just hangs - the screen stays black and the GPU fan makes a loud noise. One touch to the power button and the whole machine powers off.

I just wondered if anyone else had any experience of this or have any work arounds? I used think it was just an issue with me using my old iMac as a display but realised now its happening with my brand new 4k Benq display as well on all of its inputs.

I've tried contacting Macvidcards directly but just had radio silence from their end.

Thanks,
 

Zlobnick

macrumors member
Mar 6, 2016
55
21
Croatia
I have same problems with my flashed GTX 980. Just turn the monitor off when restarting, works fine for me :) No need to disconnect the cable.
 
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Ben Trahair

macrumors newbie
Original poster
Dec 8, 2019
3
0
Thanks I’ve tried this but it doesn’t work for me. The only way to get the machine to boot is with a switched on DVI connected monitor. I’ve also tried a DVI to DisplayPort adaptor but it only seems to work DVI to DVI on a 13 year old monitor.
 
Last edited:
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ActionableMango

macrumors G3
Sep 21, 2010
9,606
6,864
I have same problems with my flashed GTX 980. Just turn the monitor off when restarting, works fine for me :) No need to disconnect the cable.

Thanks I’ve tried this but it doesn’t work for me. The only way to get the machine to boot is with a switched on DVI connected monitor. I’ve also tried a DVI to DisplayPort adaptor but it only seems to work DVI to DVI on a 13 year old monitor.

Did you guys try setting your monitor's Display Port settings to 1.1? This usually fixes the problem.

The other problem that seems to mostly affect Macs with video cards of that era is that most DP cables are not actually VESA compliant and improperly pass through pin 20 when they shouldn't. So if the above doesn't work, then check your cable with a multimeter to see if it passing through pin 20. If it is passing through pin 20, or you are unable to check it, then I recommend trying a VESA-compliant cable that does not pass through pin 20. (Most cables are not VESA compliant, even from big name manufacturers.) Accell cables on Amazon claim to be VESA certified, but I have no personal experience with them.

FWIW, I had a Pascal MVC card (GTX980Ti) and it worked perfectly with Display Port once the monitor was set to 1.1 instead of its default 1.2.
 
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Ben Trahair

macrumors newbie
Original poster
Dec 8, 2019
3
0
Did you guys try setting your monitor's Display Port settings to 1.1? This usually fixes the problem.

The other problem that seems to mostly affect Macs with video cards of that era is that most DP cables are not actually VESA compliant and improperly pass through pin 20 when they shouldn't. So if the above doesn't work, then check your cable with a multimeter to see if it passing through pin 20. If it is passing through pin 20, or you are unable to check it, then I recommend trying a VESA-compliant cable that does not pass through pin 20. (Most cables are not VESA compliant, even from big name manufacturers.) Accell cables on Amazon claim to be VESA certified, but I have no personal experience with them.

FWIW, I had a Pascal MVC card (GTX980Ti) and it worked perfectly with Display Port once the monitor was set to 1.1 instead of its default 1.2.

Thanks I’ll check out pin 20. I get no signal at all when I switch to 1.1

I’ve just realized I may have been trying to force that to 60hz so I’ll try on 30 on 1.1
 
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ActionableMango

macrumors G3
Sep 21, 2010
9,606
6,864
Thanks I’ll check out pin 20. I get no signal at all when I switch to 1.1

I’ve just realized I may have been trying to force that to 60hz so I’ll try on 30 on 1.1

I don't think you'll find 30hz to be acceptable for use, but it will be an interesting test.

A third possibility I didn't think of until now is that it is not unusual for MVC knockoff cards to not have all ports working correctly because the person who copied it used the ROM on a different model card. Did you buy directly from MVC?
 
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