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VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
just wanna let you know that i just installed
1 rx 580 in pci slot 2 and is 2,5 slots wide and
1 rx 480 in pci slot 1 and is 2 slots wide
they are both asus strix 8gb 3 fans each in a mac pro 5,1
i had to remove the plastic cover that is in the metal division between the cpu cage and the pci area
also i had to put a little toothpick in between the card just to give it enough clearance for the fans to don't touch at all.
im using just the normal pcie booster so far no crashes

its a monster setup.
2 x 3.46ghz xeon
96gb ram
double gpu
not bad

now i can actually play solitary in extreme mode.
 

VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
I ended up returning the RX 480 8gb (i just bought it used, super cheap) because it was making my final cut pro X crash. im not sure if there was something wrong with the GPU or fcpx just can't be completely stable with 2 gpus. having 2 rx 480 580 8gb gave a score in luxmark of 29,555 points. but i bruce X benchmark it was pretty much the same, around 19sec. either with 1 or 2 gpus. how sad.
 

h9826790

macrumors P6
Apr 3, 2014
15,663
7,865
Hong Kong
I ended up returning the RX 480 8gb (i just bought it used, super cheap) because it was making my final cut pro X crash. im not sure if there was something wrong with the GPU or fcpx just can't be completely stable with 2 gpus. having 2 rx 480 580 8gb gave a score in luxmark of 29,555 points. but i bruce X benchmark it was pretty much the same, around 19sec. either with 1 or 2 gpus. how sad.

FCPX can be very stable with 2 GPUs, in fact, the Mac Pro 6,1 only has dual GPU options, and it's almost a FCPX machine. Also, I ran with dual 7950 for quite a bit of time. It's completely stable and perform very well in FCPX (15s BruceX).

Too bad that it doesn't work with 480 + 580. I am thinking if dual 580 (or dual 480) can work fine in FCPX. Or it's even that particular Asus Strix card not working well with cMP.
 
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VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
not sure whats the exact problem. im thinking its gotta do more with final cut pro x and high sierra making it unstable. that was my whole reason for having dual gpu. i was thinking bruce x will be muuuuch faster but is not. so im not sure whats up. i already returned it tho. it was a very very tight fit tho with the cards that i had. the rx 580 asus strix its a monster. thats the one i kept.
 

itdk92

macrumors 6502a
Nov 14, 2016
504
180
Copenhagen, Denmark
FCPX can be very stable with 2 GPUs, in fact, the Mac Pro 6,1 only has dual GPU options, and it's almost a FCPX machine. Also, I ran with dual 7950 for quite a bit of time. It's completely stable and perform very well in FCPX (15s BruceX).

Too bad that it doesn't work with 480 + 580. I am thinking if dual 580 (or dual 480) can work fine in FCPX. Or it's even that particular Asus Strix card not working well with cMP.

Dual RX 580 work fine and with no crasv or problem, including fcpx

GPUs needs to be paired in macOS for best reliability and performance
 
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VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
Dual RX 580 work fine and with no crasv or problem, including fcpx

GPUs needs to be paired in macOS for best reliability and performance

what you mean they need to be paired in mac os ?

i had asus strix

rx 580
rx 480

now i only have

rx 580
 

AndreeOnline

macrumors 6502a
Aug 15, 2014
575
360
Zürich
You need identical GPUs. Not mix and match.

RX580 ≠ RX480

Two of one OR the other would be fine.

I’m not 100% sure they need to be the same brand and model, but why mix it up? I’d definitely go for identical cards all the way.
 

VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
Is that actually proven somewhere ? Maybe it was just a defective rx 480. That’s what I tought.
I have read that even Mac Pro 6,1 owner are having problems with High Sierra FCPX and crashes
 

VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
Reason I bought the card is that it was extremely cheap. Aprox 157 usd. Asus strix rx 480 8gb. But I think it was defective since the heat sink had been removed and now because of the crashes. I had a 5770 and my strix 580 and no crashes.
 

AndreeOnline

macrumors 6502a
Aug 15, 2014
575
360
Zürich
Yes, well the Mac itself has no problems with mixed cards of course.

Other apps might also be able to benefit from dual cards. DaVinci Resolve will use both cards if you check "Use GUI card for acceleration", but performance will be limited by the weaker card—especially the amount of RAM. A 3GB and a 11GB graphics card in Resolve would net you 3GB: the lowest common denominator.

In terms of FCPX, one can imagine that since the only official dual gfx configurations are those from Apple using identical cards, there might be some optimisations that only kick in when two identical cards are recognised.

At any rate, we've seen quite a few examples with different cards where it seems apparent that not both cards were used. But this is a pretty old topic now and I don't have any links at hand. It's just something I've filed under "lessons learned", personally.

EDIT: and we've also seen examples of two identical, non standard cards, working.
 
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devon807

macrumors 6502
Dec 31, 2014
369
95
Virginia
Is that actually proven somewhere ? Maybe it was just a defective rx 480. That’s what I tought.
I have read that even Mac Pro 6,1 owner are having problems with High Sierra FCPX and crashes
I tried it with an RX 560 and the 5770, no go. BruceX was at 30 ish seconds. Two RX 560's did BruceX in 19seconds.
 

VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
Hello. Can someone share a a test of double (dual) rx 580 in Final Cut Pro x Bruce x?

I’m thinking in going dual. (Already have a ASUS strix rx 580 8gb)
My main use is FCPX.
So I wanna see if there is real benefits of this or it’s only to brag


Thanks!
 

VillasManzanill

macrumors regular
Original poster
Mar 7, 2012
133
18
Hello

Anybody has a Bruce X test of two (dual) rx 580
I’m interested in buying a second gpu if it’s worth it for FCPX. Thanks!
 

fatespawn

macrumors regular
Feb 22, 2009
207
102
Chicagoish
I'm about to do the same thing to my Mac Pro. I have an RX480 in another computer that I'm going to swipe and put in my Mac Pro. Does anyone have a link to the power connector that will be required to get this sucker up and running. I still have my stock GT120 and will probably just keep it in there if I ever need a boot screen for some reason. Any links? TIA.
 

h9826790

macrumors P6
Apr 3, 2014
15,663
7,865
Hong Kong
I'm about to do the same thing to my Mac Pro. I have an RX480 in another computer that I'm going to swipe and put in my Mac Pro. Does anyone have a link to the power connector that will be required to get this sucker up and running. I still have my stock GT120 and will probably just keep it in there if I ever need a boot screen for some reason. Any links? TIA.

Reference RX480? How many connector / pin on the card?
 

SneakyTLoD

macrumors member
Apr 6, 2018
72
30

fatespawn

macrumors regular
Feb 22, 2009
207
102
Chicagoish

Thanks. Works like a champ! Even properly identified by the OS. I guess that's been fixed from what I've been reading.

RX480.jpg
 
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