For 2006 & 2007 models (Mac Pro 1,1 & 2,1): The best approach will be to use his method to install one 5770 in slot 1 (the bottommost slot that accommodates a double width PCIe card), and the second 5770 in Slot 4. This will use the two fastest PCIe lane combinations (x16 in slot1 and x8 in slot 4), and allow for increased ventilation, as well as leaving slots 2 and 3 open for other add-on cards. The only drawback here is the loss of Drive Bays #3 and #4 to make room for the double width 5770 on the top in PCIe slot 4.
For 2008-2012 (Mac Pro 3,1 // 4,1 // 5,1): Unfortunately only Slots 1 and 2 can run at full speed and and use x16 lanes of the PCIe bus. The top two slots (#3 & #4) will only run at x4 lanes. In the 2008 model the top two x4 slots are further reduced to PCIe revision 1 speeds. Therefore to optimize performance from GPUs in Mac Pros 3,1 // 4,1 // 5,1 both GPUs need to be in the bottom two slots (PCIe slots #1 and #2). This unfortunately reduces ventilation and blocks PCie slot #3. Many people however have run two GPUs stacked close together in this configuration without overheating problems so it doesn't seem to be a major issue.
(I've posted this same reply on the Dual GPU thread I started as well to try and keep things on topic since my reply here has little to do with the Bruce X benchmark directly. Apologies mods!)
Just installed 2x 7950's using Y splitters (yikes) powering 2x 27"LED cinema displays on the bottom card.
Model Name: Mac Pro (Early 2008)
Model Identifier: MacPro3,1
Processor Name: Quad-Core Intel Xeon
Processor Speed: 2.8 GHz
Number of Processors: 2
Total Number of Cores: 8
L2 Cache (per Processor): 12 MB
Memory: 32 GB
BruceX test - ProRes422 - average over 3 runs
1x 7950 - 50 secs
2x 7950 - 32 secs
Has anyone tried dual GTX570s or should I change to a single GTX770 or R280x? I edit 45 min rugby videos for my childrens team with Crumplepop Tonegrade, a few audio filters and exporting takes ages. Anything to speed it up!
Grabbing a r280x (or 2nd hand 7970) would make a lot more sense I think. You should easily get down to sub 30sec on a single card with significantly lower power consumption (compared to the dual gtx570s) and a 770 won't come close. Sell that 570. Having said that I'm sitting on one I need to sell- always seems so much easier to buy.
Darren I'm surprised by your times. Your dual 280s are producing similar if slightly slower speeds compared to my single 7970s. Is mavericks throttling them? Do the fans increase in volume under load? I ask this because my Mavericks install initially heavily throttled my 7970. I still don't quite know why. The nvramdynlib fix for imessage seems to have sorted it out as a side effect. Throttled I got luxmark (2.1 sala) scores in the 1500 region and now at full tilt I get +2400.
It's good to know that fcpx is playing ball with dual cards in a hack.
I was in the Apple Store a few days ago and they had the base model New Mac Pro (2013) on display. Since it had FCP X installed, I took it upon myself to run BruceX. The bad news is it had FCP X 10.0.9. Since I didn't have the App Store User/Password I couldn't update it.
FCP X 10.0.9
New Mac Pro (R2D2)
Intel Xeon 3.7GHz Quad Core
12GB DDR3 RAM
Dual AMD FirePro D300 2GB
256GB Flash HD
I had three different video cards to try out....Below are the results in case anyone finds the info useful. This thread has been very helpful to me in figuring out which card(s) to buy to use with 10.1 and my 2008 Mac Pro. Thanks everyone!
My machine which I used for the test
Early 2008 MacPro 3,1
2 x 2.8 GHz Quad-Core Intel Xeon
14 GB RAM
750 GB hd 7200rpm
FCP X 10.1.1
Dual Nvidia Quadro 4000 GPU
BruceX, ProRes 422 = 43 seconds
Dual Sapphire Radeon 7700 GPU
BruceX, ProRes 422 = 42 seconds
Single Sapphire Radeon 7950 OC w/Boost GPU
BruceX, ProRes 422 = 118 seconds
The Radeon 7700s are a nice value because I found them on Amazon for $100 a piece and they had a rebate which brought them down to $85 each. The only problem is that the Mac Pro would crash on wake
(common problem - Apple forums)
, which makes them frustrating to keep. So they are going back...
The Radeon 7950 was a surprise. I thought it would perform better than it did. Pretty disappointed in it.
It appears that if you have dual GPUs and an old Mac Pro, definitely get yourself a dual GPU setup. Does anyone else on here have any experience with the 7700s? I'm guessing no since I did a search on here and the ENTIRE internet, and found no one else with a genuine (non x86) Mac using a 7700.
I seem to be getting that hideous export error with this benchmark file, anyone else have this issue with it ? I tried cleaning out all the preferences and the usually crap that causes this but no luck. Everything else works fine on my system but this ...
Yeah the h264 export fails it worked once , then never again ...
Speeds are pretty decent although machine gets more loud from the heat that previously when loaded. I was debating buying a new machine but for me a replacement would run at least 8K for a suitable replacement where i would see sufficient gains to justify replacing my machines ( although not having thunderbolt really does suck ) I have it on my notebooks so i'll make due for now. But 25dlrs for a powersupply + another video card not a bad deal for the perf gains . Although anyone doing it , plan accordingly , 8 or 6 PIN PCI-E power cables will not run though where the sata cable goes though, you do need to splice them and you need atleast 12-15 inches of wiring to extend to reach where everything will screw back together ( backing plate behind the 5.25 will not go back in other wise )
On another note , i saw your 7950's score and it seems off , i have another machine with a 7950 that i use for programing, in most benchmarks i've ever ran to compare the 7950 vs the 7970 it's usually never more than 20% off . I would check your PCI-E speeds or power , if the GPU has been clocked down ect .
Both the DH and the 2DH would boot succesfully when they were the only GPU installed, but with both installed together no output would come out of either card, and at one point my 3,1 would just keep on trying to restart over and over again with the apple chime until a hard power down was applied.
Perhaps the fact that even though these are both 7770s but in different configurations might have been the culprit.
Either way I'm going to keep them for my 1,1 tinker box since they cost less (combined) than the apple 5770 I was about to purchase for the 1,1.
For my 3,1 it seems the best bet for reliability is still dual 5770s.
Good luck and thanks again for sharing your findings!
The different configurations could indeed be the culprit. Either way, they aren't an option for Mac Pros 3,1 it seems like. I used the
Sapphire Radeon HD 7700s
. Both are identical, but I can't keep them with that wake bug. I may just end up using the 5770s since they are tried and true.