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ZombiePhysicist

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May 22, 2014
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I need to get 2 video cards in my Mac Pro 5,1. Problem is the Mac Pro has only 2 power cords, and most modern video cards need two power cords.

So question is, what are the most powerful cards that require only one power cord. Super bonus points if the cards are single slot.

The original ATI 5770s only require one plug and you can get 2 of them in there. Question if there are more modern cards that can do this?

I think the AMD Radeon R9 Nano would work, power wise, but does anyone know if it will work in the Mac Pro?
 
I am now running dual 7950 with internal power only. Not exactly what you want. But I can tell you that by running at stock 800/1250MHz, and lower the voltage as much as possible.

Both card runs stable and quiet for a year now (including heavy crossfire 4K gaming in Windows which push both GPU to above 90% continuously).

In my experience, I found that some 7950 draw more power from the slot, the other may draw less (but more from the cable). It's hard to tell which one is the best. But I can say that if you get a card that can draw >40W from the slot, then it can easily run both 7950 with internal power only without go over the 75W 6pin limit.

For normal use in OSX (including 4K rendering in FCPX), but not benchmark / Furmark. The card rarely draw more than 65W, and one of my card can draw more from the slot, so that it demand less from the cable, which keeps the power draw always lower then 75W.

However, if you don't need the boot screen (with low cost), there is not much benefit to run this config now. I am sure a single new high end GPU can do better then 2x 7950 in some task.

May I know why you need 2 graphic cards? You need to power lots of screen? (More then 6)

I think the Nano only works in the Sierra beta as an eGPU with the nMP at this moment. Not a real option for cMP yet.

https://forums.macrumors.com/thread...mac-with-2-d700s.1732849/page-5#post-21722712
 
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I need to run 6 30" cinema displays, so they need dual-link.

I was driving a single vision 7870 vision tek card for 9 months or so, worked great. Then randomly, it stopped driving more than 3 ports. I can run any 3 monitors, in any 3 ports, but if I try to plug in a 4th or more monitor, all the displays go wonky randomly blacking and and trying to recycle to no avail. Unplug all but 3 displays, and it works great.

It's beyond bizzare. At first I thought that the card died, so I bought another one, same thing. So maybe its the motherboard or power supply? Really at a loss, but I need to get my 6 screens going. :(
 
I need to run 6 30" cinema displays, so they need dual-link.

I was driving a single vision 7870 vision tek card for 9 months or so, worked great. Then randomly, it stopped driving more than 3 ports. I can run any 3 monitors, in any 3 ports, but if I try to plug in a 4th or more monitor, all the displays go wonky randomly blacking and and trying to recycle to no avail. Unplug all but 3 displays, and it works great.

It's beyond bizzare. At first I thought that the card died, so I bought another one, same thing. So maybe its the motherboard or power supply? Really at a loss, but I need to get my 6 screens going. :(

I see, then this dual 7950 setup should works well, and should be more stable then a single 7870.

Even though I am not sure what will happen with dual GPU to power 6 screen. However, it's clearly a that single 7950 can drive 3 non 4k monitor without any problem. Since the nMP can drive 6 screens. So I think I can safely assume that the there is no restriction in the OSX side but just the graphic card or driver's problem in your case.

If you want to have boot screen, and don't want to do any PSU mod. At this moment, I can't think of another easier, cheaper, but more powerful setup then dual 7950.

Dual 7970 is more powerful, but quite impossible to power them without power mod (or more precisely, only by that 2x 6pin source).

From my study, the 680 also draw more power then the 7950. Also, I don't think you can be easily under volt the card + flash Mac EFI. Since the under volt 7950s are already right at the edge of the power consumption that the 2x 6 pin can deliver, I think dual 680 is also not quite possible without PSU mod.

If no need EFI (or don't mind to pay for it), and don't mind to deal with the web driver, may be dual 750 Ti or dual 960 is also work. But AFAIK, it's not necessary more powerful then dual 7950. With total 4GB VRAM on these 2 maxwell card vs 6G VRAM on the 7950 (to drive 6 screens), and no significant performance improvement, and no free EFI option, and no native OSX driver support. I personally don't think this is a good option.

Anyway, if you want to know more about my setup. Please feel free to tell me. However, I cannot run the 6 screens test for you.
 
Even though I agree that the GT120 is a very handy card in the cMP, but the cheapest good condition GT120 I can get still cost about $100. I think it's not worth at this moment. Unless I need to run the 2nd GPU with the GT120 installed. Otherwise I may just keep my 7950 in the box as a backup.
 
Instead of a GT 120 you could use a new cheap GT 630 (GK107 Kepler chip in the link below, actually an HP Nvidia OEM model, has two DP 1.2 and one DVI connector): http://www.macvidcards.com/store/p80/Nvidia_GT_630_2_GB.html

If the card is only for display 2D graphics.

I'm using a PC version of that HP Nvidia GT 630 for eGPU with a Mac Mini, works like a charm with OS X drivers, in my opinion the successor of GT 120.

http://www8.hp.com/us/en/products/hpe-oas/product-detail.html?oid=5285071

Passmark:
GT 120 -> 301
GT 630 -> 793 (2.6 times faster than GT 120)
 
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I need to get 2 video cards in my Mac Pro 5,1. Problem is the Mac Pro has only 2 power cords, and most modern video cards need two power cords.

So question is, what are the most powerful cards that require only one power cord. Super bonus points if the cards are single slot.

The original ATI 5770s only require one plug and you can get 2 of them in there. Question if there are more modern cards that can do this?

I think the AMD Radeon R9 Nano would work, power wise, but does anyone know if it will work in the Mac Pro?


If you can wait, the option above may work very well. In case you can't wait, you could have a look at two Nvidia Quadro 4000 PNY Mac Edition aftermarket cards. - You would have full support and no driver issues or flashing. They are single slot and only need one power cord per card. It would be a workable setup that matches your requirements, however it also depends on your eBay skills and timing to source two cards on a low budget to make it economically feasible.
The performance of those cards are medium level, I think comparable to the ATI 5770 with a small cuda bonus. - Nothing fancy but workable.
 
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Amazed that anyone can charge $100 for the GT120. I can get a Radeon 6900 series for that much.

I don't think anyone should pay more than $50-60 for a basic bootscreen card.
 
Instead of a GT 120 you could use a new cheap GT 630 (GK107 Kepler chip in the link below, actually an HP Nvidia OEM model, has two DP 1.2 and one DVI connector): http://www.macvidcards.com/store/p80/Nvidia_GT_630_2_GB.html

If the card is only for display 2D graphics.

I'm using a PC version of that HP Nvidia GT 630 for eGPU with a Mac Mini, works like a charm with OS X drivers, in my opinion the successor of GT 120.

http://www8.hp.com/us/en/products/hpe-oas/product-detail.html?oid=5285071

Passmark:
GT 120 -> 301
GT 630 -> 793 (2.6 times faster than GT 120)

Thanks for the suggestion. However, the shipping cost will make it much more expensive then $100 for me.

Anyway, do you know if this card can work with the Maxwell card together in Windows? I think the GT120 cause some issues in Windows 10. If this card can co-exist with the Maxwell card (and hopefully the 10xx series) without any driver issues in Windows, then may be it worth that price for me.
 
Thanks for the suggestion. However, the shipping cost will make it much more expensive then $100 for me.

Anyway, do you know if this card can work with the Maxwell card together in Windows? I think the GT120 cause some issues in Windows 10. If this card can co-exist with the Maxwell card (and hopefully the 10xx series) without any driver issues in Windows, then may be it worth that price for me.

No because Windows 10 attempts to roll back the Nvidia drivers to an older version that isn't Maxwell compatible.
 
No because Windows 10 attempts to roll back the Nvidia drivers to an older version that isn't Maxwell compatible.

I disagree. GT630 (Kepler GK107) should co-exist fine with a Maxwell card. Not like the very old GT120.

Note: There are even newer GT630 with GK 208 chip, but I don't know if native OS X drivers will support that chip (without Nvidia web drivers).
 
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If you can wait, the option above may work very well. In case you can't wait, you could have a look at two Nvidia Quadro 4000 PNY Mac Edition aftermarket cards. - You would have full support and no driver issues or flashing. They are single slot and only need one power cord per card. It would be a workable setup that matches your requirements, however it also depends on your eBay skills and timing to source two cards on a low budget to make it economically feasible.
The performance of those cards are medium level, I think comparable to the ATI 5770 with a small cuda bonus. - Nothing fancy but workable.

Thanks. Seems like if I want ease of use installation I'm going old school with this (or might as well just use the 2 5770 cards I have. (I gave one card to a buddy, but will scrounge it back to see if they solve the problem).

Or going the 7950 route and hoping to keep things on the cusp of not using too much juice.

Good lord would it be great for apple to update the mac pro. This is all kinds of suck.

Thanks guys, this has been helpful. I'm going to try some of your suggestions and see what happens.

Still one one of the craziest failures I've ever had on a computer system. Just bizarre.
 
I use the GT120 alongside my 980Ti. I just disabled the GT120 inside Windows Device Manager, and then I'm able to install drivers for my Nvidia 980Ti :)
 
I use the GT120 alongside my 980Ti. I just disabled the GT120 inside Windows Device Manager, and then I'm able to install drivers for my Nvidia 980Ti :)
Yeah that's one way around it. I tried it a year ago when Win10 was released but it kept forcing the installation of the GT120 even if I disabled it. The behaviour probably changed since then because Microsoft isn't supplying Nvidia drivers anymore via Windows update.
 
I disabled it, and Windows Update still updated the driver. But when I removed the driver for the 2nd time after I disabled it, it didn't install it. And it haven't done it since. :)
 
The card in my sig will drive 3 screens no problem. Single slot, board powered, no extra connection needed.
 
Finally get a GT120. Not mean to do that, but when when I got my logic board replacement, I got a whole Mac Pro that come with the GT120. So, I can install both GT120 and 1080Ti at the same time.

To stop Windows 10 automatically install the GT120 driver is easy. However, what I realise is even if I disable GT120 in device manager. The card is still powered. In fact, not just powered, but high power consumption as well. It seems without proper driver. The card won't be able to enter low power state. Therefore, keep drawing power, and stay at about 70C (with proper driver, the card usually run below 60C at real idle).

May I know how you guys deal with this problem? Or there is a specific sequence to avoid this issue (e.g. install GT120 driver, disable GT120, then install 1080Ti driver, etc.)
 
Finally get a GT120. Not mean to do that, but when when I got my logic board replacement, I got a whole Mac Pro that come with the GT120. So, I can install both GT120 and 1080Ti at the same time.

To stop Windows 10 automatically install the GT120 driver is easy. However, what I realise is even if I disable GT120 in device manager. The card is still powered. In fact, not just powered, but high power consumption as well. It seems without proper driver. The card won't be able to enter low power state. Therefore, keep drawing power, and stay at about 70C (with proper driver, the card usually run below 60C at real idle).

May I know how you guys deal with this problem? Or there is a specific sequence to avoid this issue (e.g. install GT120 driver, disable GT120, then install 1080Ti driver, etc.)


You can not install any Nvidia driver for the GT-120 if you also want to install the drivers for your 1080 TI. (I'm sure you do). They are completely incompatible and you will get black screens from both cards. Booting into safe mode and deleting the GT-120 driver resolves the issue.

I run the MS Basic Display Driver for my GT-120 and the card works fine with no compatibility issues with my 1080 TI's. If the card can't fall back to low power mode it's not really a problem as the card draws little power anyway. The best way I have found to keep windows from continually trying to install the bad Nvidia driver for the GT-120 (Yes, even with the card disabled) is to use Group Policy. Using gpedit you can block driver updates for only the GT-120.

Running a GT-120 and dual 1080 TI's in perfect harmony in Win 10 and macOS.

Oh, also, the GT-120 is attached to my 10" boot screen display. It works great as a second display while in Win10 or macOS.

Here a How-To and it worked great without blocking any other updates.

https://www.howtogeek.com/263851/ho...from-automatically-updating-specific-drivers/
 
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You can not install any Nvidia driver for the GT-120 if you also want to install the drivers for your 1080 TI. (I'm sure you do). They are completely incompatible and you will get black screens from both cards. Booting into safe mode and deleting the GT-120 driver resolves the issue.

I run the MS Basic Display Driver for my GT-120 and the card works fine with no compatibility issues with my 1080 TI's. If the card can't fall back to low power mode it's not really a problem as the card draws little power anyway. The best way I have found to keep windows from continually trying to install the bad Nvidia driver for the GT-120 (Yes, even with the card disabled) is to use Group Policy. Using gpedit you can block driver updates for only the GT-120.

Running a GT-120 and dual 1080 TI's in perfect harmony in Win 10 and macOS.

Oh, also, the GT-120 is attached to my 10" boot screen display. It works great as a second display while in Win10 or macOS.

Here a How-To and it worked great without blocking any other updates.

https://www.howtogeek.com/263851/ho...from-automatically-updating-specific-drivers/

Thanks for the sharing.

The auto driver update is already blocked. That’s not an issue for me.

However, I wonder if there is any way to stop the GT120 seats there at above 70C which is not even enabled.

Anyway, good suggestion. I will boot to safe mode. Disable it, and then see if the normal mode still warm up the card if driver is never loaded.

I don’t mind it draw more power, especially I am just running single processor cMP. PSU is not a problem at all. However, even though this card is rated up to 105C. I don’t want it sits at above 70C if normally only 55C.

If this is already the best I can get, I will still take it.
 
However, I wonder if there is any way to stop the GT120 seats there at above 70C which is not even enabled.


I think this surprised me the most. Even with the card disabled in device manager it still drives a display just fine. I wasn't expecting that.

Congrats on getting your cMP back up and running !
 
I think this surprised me the most. Even with the card disabled in device manager it still drives a display just fine. I wasn't expecting that.

Congrats on getting your cMP back up and running !

No, I didn't get the display from it if disabled. However, MacsFanControl can still read it's temperature sensor's reading.
 
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I think this surprised me the most. Even with the card disabled in device manager it still drives a display just fine. I wasn't expecting that.

Congrats on getting your cMP back up and running !

Update 1: I can actually get display from the disabled GT120. 100% sure. I just tested it. You may try it yourself.

If I didn't connect the display to the GT120 during boot, then after I boot to desktop, I won't get anything if it's disabled.

But if I let the GT120 display the boot screen from the very beginning. The card actually can continue display even I boot to desktop. And I can use the GT120 to display the device manager to show that itself is disabled. Very interesting. I bet that's because of the EFI still working. In fact, the screen is accelerated as well.

Now it make sense. The card always working, never stop (even disabled). And due to lack of proper driver support, it's actually operating in high power setting (even at idle). Therefore, the temperature sensor still working and transmitting temperature to MacsFanControl. And stay at about 70C.

GT120 disbaled + 70C.JPG


And once the card is disabled. I can remove all the auto update block. The card will keep disabled on the next boot. And I don't need to worry about other hardware's driver update.

I am now wonder if we will get this in 10.14 as well. As long as the EFI is working, we can get the normal accelerated display (but UI rendering may be a problem if METAL is really required).

 
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