Double Precision, the Titan, and OSX

Discussion in 'Mac Pro' started by MacVidCards, Nov 20, 2013.

  1. MacVidCards Suspended

    Nov 17, 2008
    Hollywood, CA
    In the GPGPU world there is a thing called Double Precision Floating Point.

    Quadro and Tesla cards have had this enabled while their Fermi brothers did not.

    Unfortunately, there were (are?) no common apps that are able to benefit from it.

    So when I sent Barefeats my fabulous Quadro 6000 and Tesla C2070 they performed like the down clocked GRX480s they are at heart. Basically like a GTX470. I was hoping he'd find SOMETHING that could benefit from this ability, as I'm sure NVIDIA would have liked Quadro 4000 to have shined somewhere instead of performing like a GT450/GTX460.

    Flash forward to 2013, NVIDIA includes a control panel feature that bumps DP Gigaflops from 230 or so to 1400-1500 in Titan in Windows.

    At the same time the clocks get lowered so Single Precision DROPS.

    Netkas started bugging me a couple weeks ago about DP on Titan using EFI rom. He couldn't enable it in Bootcamp. I misunderstood and told him DisplayPort worked fine. He kept on about it until I understood.

    I confirmed that it didn't work for me either. I keep a rig that is nearly identical to his for testing consistency.

    Then he noticed something unusual, he made a few fixes to the rom and it started working in Win 8.1 64 bit.

    And even more interesting, when he booted back to OSX, THE ENSBLED DP KEPT WORKING THERE TOO.

    I went back to a PC only Bios and confirmed that it worked on my 3,1 as well.

    And then it was my turn to discover something. NVIDIA was doing something never done before. When you enable DP via the control panel in Win, IT REFLASHES THE TITAN WITH A MODDED ROM.

    And it doesn't just change one section, it changes 2 of the 5 parts.

    It is odd that they don't mention this. It is possible that if you crashed machine or lost power that card would end with half finished mod and be borked. While EFI roms used to have 2 parts, now with 5 they are much trickier. They all have to mesh like gear teeth and have little checks to make sure no changes take place.

    In any case, when we wrote original Titan EFI we never planned on a Windows control panel surreptiously re-writing the ROM. So, the Titans done so far were not made compatible with this mod.

    And here is where it gets even weirder. The rom that Netkas fixed and let's him change at will DOESNT WORK FOR ME. I have tried on 4 different Titans so far. I updated my 4,1 to Win 8.1 64 but haven't downloaded the 4 GB update on my 3,1. This is the last remaining thing to test.

    So, currently I do not believe that EFI Titans delivered thus far will work this way. I have done less than 10 of them so this doesn't affect very many people. The last 4 I sent out have the rom that works for Netkas but not for me.

    So, hopefully soon I will find the final piece of the puzzle. There is some other part I can't see yet but I will find it. The GK110 was hardest EFI we have done. But we will get last piece figured out.

    And as I have mentioned I don't know of any current OSX software that uses this so it is little more than a curiosity right now.

    When I get this last puzzle solved, anyone with a Titan done by us will be able to send card back for free mod.

    I suppose it would be helpful to gather more info.

    Anyone with a Titan in a Mac Pro that has Bootcamp should try this. There is a tiny chance you could brick card, we can fix that for US folks if it happens.

    Would be useful to gather what cards work in what Mac Pro using what OS and Nvidia drivers.
  2. netkas macrumors 65816

    Oct 2, 2007
  3. MacVidCards thread starter Suspended

    Nov 17, 2008
    Hollywood, CA
    I think you mean GK110b vs GK110.

    I haven't been checking for that, but will have another one here tomorrow.

    Interesting thought. Just got first report of trouble that might be "b" related from. 780 I did last weekend. Is having trouble with RCX. I am having him try OpenCl as folks on your board have started thread with issue on b cards. I got 22 780s in last week, none were "b"a except one I did over weekend.
  4. Gav Mack macrumors 68020

    Gav Mack

    Jun 15, 2008
    Sagittarius A*
    So if it reflashes the rom enabling DP, i presume it asks for a restart to enable it. Must admit I've never heard of a re flash being done surreptitiously without the users consent on a graphics card for ages, Matrox springs to mind with something 15 years ago ish and a voodoo 3d add on card which said a driver only even earlier than that - when I had hair and that was a single rom for those and not two!
  5. macrumors member

    Oct 2, 2013
    Nice news now that I pulled the trigger on a Titan
  6. Celedral macrumors 6502


    May 29, 2008
    Los Angeles
    I'll be testing that GTX 780 SC (GK110B) later tonight with OpenCL. I got this card specifically to edit r3d footage, but having no OpenCL on RC-X is such a bummer at the moment.

    I hear people are having issues with preview since it's using OpenCL. I noticed this when i previewed a video and it comes up as a incompatible file with 0kb.
  7. MacSince1990 macrumors 65816


    Oct 6, 2009
    Why would you buy a Titan over a Radeon 290X anyway...?

    And DP exists in the FPU world too =P
  8. AidenShaw macrumors P6


    Feb 8, 2003
    The Peninsula
    Because I've been burned by ATI too many times to ever get a Radeon or Firepro if there's an Nvidia alternative.

    I like my laptop Quadros.... And my workstation Quadros....
  9. beaker7 macrumors 6502a

    Mar 16, 2009
    I buy Titans over 290x because:

    A lot quieter
    A lot cooler
    Uses a lot less power
    Has more memory
    Runs all GPU compute programs available rather than a tiny subset
  10. MacSince1990 macrumors 65816


    Oct 6, 2009
    Huh. Most graphics cards I've ever had were ATI (from the ATI RAGE PRO TURBO that came with my Beige G3, to the original Radeon Mac Edition I replaced it with, to a Radeon 9000 Pro, 3650, 6490, etc)... never had any problems.
  11. AidenShaw macrumors P6


    Feb 8, 2003
    The Peninsula
    Main issue was that ATI wouldn't update drivers for new OS versions - so an OS update required a GPU upgrade.
  12. Tutor, Nov 21, 2013
    Last edited: Nov 21, 2013

    Tutor macrumors 65816


    Jun 25, 2009
    Home of the Birmingham Civil Rights Institute
    You're the Man! For greater impact, why don't you upload a pic next to it showing what OS is at play - that'd highlight the discovery to the max. I assume next you, Rominator and/or MVC will conquer that GK110b OCL issue. I look forward to that because I'm having a bunch of GTX780Ti's coming into my OctaneRender stable. My experience with using Keplers for OctaneRender in the Windows environment is that the greatest performance increase comes from increasing memory speed, and thus derivatively memory bandwidth. When my Ti's get here today with their 336 GB/sec memory bandwidth base (vs. 228 GB/sec memory bandwidth for my Titans) I'll put my experience to further testing using as a base Barefeats' Titan vs. all worthy comers testing here.
  13. MacSince1990 macrumors 65816


    Oct 6, 2009
    Ah. Yeah I suppose that's true.
  14. MacVidCards thread starter Suspended

    Nov 17, 2008
    Hollywood, CA
    New 334 OSX Nvidia Drivers have Double Precision Control Panel

    With the latest 10.9.3 Nvidia Drivers came a surprise. They added a System Preference Pane tab for "Double Precision" that allows you to turn on Double Precision performance similar to their Quadro and Tesla lines.

    We have been able to re-write our Mac EFI cards to work with this function. The DP is enabled by re-writing a small part of rom. And, the OSX implantation is slightly different from Windows but the re-writes work with each other.

    Anyhow, we have been able to update both our Titan and Titan Black EFI's to coexist with this rom writing that the System Preference Pane does.

    I am attaching a recent Double Precision benchmark.

    We will update all of our past Titans for free, provided that customer picks up the shipping. Sadly, the EEPROM chip we used doesn't work with the built in flasher, so we have to disassemble every card and change EEPROM to enable this.

    I know that there is an application that requires this as someone recently wrote me about enabling it.

    I am proud to say that Nvidia is still supporting Mac products. We will continue to support Nvidia cards in Macs as long as Nvidia does.

    It's pretty amazing how quickly the change takes effect. If you have CUDA-Z open you literally watch Double Precision performance take a nearly 10 fold JUMP.

    Attached Files:

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