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MacVidCards

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Original poster
Nov 17, 2008
6,096
1,056
Hollywood, CA
A friendly retailer who also deals with local production community has been kind enough to loan me a Cubix to get some answers.

It is a magical device, through time sharing of a sort and a pinch of pixie dust, it takes one PCIE 2 x16 lane...and turns it into four(4!).

I have been asked many times what the difference is with flashed vs unflashed cards when used in one of these babies. And now I will be able to provide the answers.

It is a massive device, requiring serious power. The later G5s had a similar power plug, means it needs more power than most computer accessories.

These cabinets are used by folks who want massive render power. The hot setup has been 4 @ GTX580s for DaVinci Resolve and Adobe AE.

My first set of testing involves 4 EVGA GTX570 2.5 cards. These are nice strong cards. You'll note that Barefeats still includes them in testing. Why? Because for some CUDA uses they equal or beat a GTX680. (And have more RAM than the Mamby Pamby 2GB card that was released)

So I included 2 flashed and one unflashed and booted up Mavericks. Cards with identical device id and board id will EFI init matching cards. And init they did. The unflashed card ran like a flashed one, but it's name was "GF100 Board" in system profiler. In OSX all 3 cards came in at PCIE 2.0/ But this was only confirmable via CUDA-Z as System Profiler did what it does when you use unflashed cards "There was an error while gathering PCI Information".

CUDA-Z reported all cards as equals.

The story changed when I booted to Windows. I will save you the pain of getting the drivers working in Windows, I still think Ballmer & Gates should be tied in room and forced to explain why changing form a 570 to a 780 back to a 570 causes Windows the conniptions that it does. In any case, with 2 flashed and 1 unflashed, the unflashed was stuck at PCIE 1.0 speed, just as if it was in Bootcamp in a Mac Pro. The other 2 flashed cards worked in PCIE 2.0 properly, switching to PCIE 1 when demand allowed them too.

So, at least for mixing cards, better to have flashed ones if booting to Windows. Next I tried HyperSli to turn my 3 @ GTX570s into a single gaming powerhouse. This required several restarts but finally they were all up and running. And, to my surprise, they were all at PCIE 2.0. I don't know if this was the SLI bridge or the Nvidia drivers, but something turned it on.

This however has not been proven stable. I brought a "tester" in to test stability using "Arkham Origins" and by the time he got the game set up, it crashed. I will continue these tests tomorrow and see if 3 flashed cards together are more stable. Will also test if unflashed cards will run at PCIE 2.0 if used by themselves.

I am planning to get a 4K display in here and do some more testing in various combos.

Imagine 4 @ 7970s for OpenCl. Could mop floor with nMP, even outfitted with Dual D700s. And if they turn out to be a $6,000 upgrade, will sell a few more Cubixs. (Cubix and 4 @ 7970s would be $4-5K, tops) SHould give you DOUBLE the OpenCl unless Apple/AMD write some handicaps into drivers.
 
If they would be able to use both x16 host ports, would be much better, like having every card on pcie 1.0 x16
 
Some results using Valley Benchmark

Major caveat...the only way I could get Windows to take Crossfire with 7950/70 was to turn OFF the EFI rom.

Someone else has been posting here about this so I am going to investigate further.

The SLi wasn't fun either. Eventually I was able to get several card combos going.

The two AMD tests are Crossfired 7950 and 7970. The 7970 did 5 fps better but oddly had a lower minimum fps.

It took 3 @ 570s 2.5s to ALMOST keep up with a GTX780 Duo.

Was easier for the 580 Duo.

Don't have any Titans today, they tend to not stay around.
 

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