1. Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

PhysX - Which dedicated card is powerful enough?

Discussion in 'Graphics Cards' started by newtekie1, May 30, 2010.

  1. newtekie1

    newtekie1 Semi-Retired Folder

    Joined:
    Nov 22, 2005
    Messages:
    19,484 (6.35/day)
    Thanks Received:
    5,725
    I've seen a few outragous claims about what is required for a dedicated PhysX card. So I decided to do a quick test with what I had laying around to see.

    The two biggest things I've seen are:
    • A 128-bit makes the card too slow.
    • A G92 w/ 112 shaders is needed.

    Ok, this is just a quick test, using Batman:AA, because it is the holiday weekend, and I didn't want to spend hours pulling machines apart and benchmarking every combination I could.

    Test setup:

    Xeon X3370@3.6GHz
    RAM: 8GB PC2-800 4-4-4-12
    eVGA 780i
    Primary GPU: GTX470@800/1600/900(c/s/m)
    PhysX GPU: 9600GT
    PSU: Corsair HX850


    Column 1 Column 2 Column 3 Column 4
    0 Min FPS AVG FPS Max FPS
    1 PhysX Disabled 74 128 186
    2 CPU PhysX 11 17 26
    3 GTX470 32 61 102
    4 GTX470+9600GT 32 61 102
    5 GTC470+9600GT UC * 27 58 102


    Some interesting results. There was no change by adding the 9600GT, kind of odd, I expected better performance. So that by right there tells me the GTX470 is powerful enough to do PhysX in Batman itself. I'd try again with Metro, but I can't find an accurate way to benchmark it easily. To me this confirms also that when PhysX is enabled, at least with Batman, performance is purposefully limitted, probably to meet a target framerate to ensure smooth gameplay.

    Now, in the last test, I underclocked the 9600GT as low as possible, both the core, shaders, and memory. I did this to see how a much weaker card, with far less memory bandwidth would perform. There was almost no difference, but it did finally show a little performance difference.

    There are also other users that report great results with 128-bit cards. Erocker uses a GT240 with his HD5850s in crossfire and reports good results.

    Now, what is my conclusion? You don't need a powerful GPU for PhysX. PhysX relies more on the shader power of the GPU then the memory bandwidth. Remember, the original PPU only had a 128-bit bus.

    I think the minimum I would recommend for a dedicated PhysX card is a GT220, or 48 shaders. I would not recommend anyone with a decently powerful nVidia card already to waste any money on a dedicated PhysX card. Anything from the GTX200 or GTX400 series is enough, don't waste your money. For anyone with an ATi card wanting a dedicated PhysX card, do not spend a large amount of money, and don't worry about getting a high performance card, go by the minimum I set above. For the small number of games that would even use it, it isn't worth spending more then $50 on a card.
    Crunching for Team TPU 25 Million points folded for TPU
  2. erocker

    erocker Super Moderator Staff Member

    Joined:
    Jul 19, 2006
    Messages:
    39,137 (13.83/day)
    Thanks Received:
    13,585
    I completely agree with you. GT 220's and 240's make great PhysX cards. They are generally smaller cards that won't restrict airflow to your main GPU's and they don't require an external power connector. If anything, having the PhysX card in my machine has dropped the temp of my 2nd GPU due to the PPU card cooling the backside of the GPU. Power consumption at idle went up a mere 12 watts.

    Attached Files:

  3. Loosenut

    Loosenut

    Joined:
    Jan 14, 2010
    Messages:
    843 (0.54/day)
    Thanks Received:
    169
    Location:
    Montreal, Qc. Canada
    Thank you for the brief review Newtekie, you may have saved me a few bucks :toast:

    EDIT: nice rig you got there Erocker
  4. Lionheart

    Lionheart

    Joined:
    Apr 30, 2008
    Messages:
    4,004 (1.84/day)
    Thanks Received:
    790
    Since that News about using a Nvidia card with ATi GPU's, ima grab me a GT240, feels like the perfect card for a dedicated PhysX card:toast:
  5. $immond$ New Member

    Joined:
    Nov 30, 2009
    Messages:
    394 (0.25/day)
    Thanks Received:
    22
    Location:
    Edmonton
    Even if Nvidia decides that they want a monopoly on the physx technology, I am sure we will find away to modify the drivers.
  6. devguy

    devguy

    Joined:
    Feb 17, 2007
    Messages:
    1,239 (0.47/day)
    Thanks Received:
    171
    Location:
    SoCal
    My friends that have done this ATI + nVidia combo all agree that the perfect PhysX card is the 8800GS (96 stream processor 9600 gso). It does take an additional pcie connector though. I'm intrigued that a GT220 is good enough. Good info!
  7. $immond$ New Member

    Joined:
    Nov 30, 2009
    Messages:
    394 (0.25/day)
    Thanks Received:
    22
    Location:
    Edmonton
    I would only settle for a 9800 GT
  8. erocker

    erocker Super Moderator Staff Member

    Joined:
    Jul 19, 2006
    Messages:
    39,137 (13.83/day)
    Thanks Received:
    13,585
    Min: 49 fps
    Max: 112 fps
    Avg: 92 fps

    All settings maxed, PhysX on high

    Watching the bench I don't even notice any slowdown, everything is smooth as butter. Considering it doesn't even use any more than 50% of the physics card, a GT 220, maybe even lower would be fine.
  9. KainXS

    KainXS

    Joined:
    Sep 25, 2007
    Messages:
    5,598 (2.34/day)
    Thanks Received:
    501
    I have heard that people use underclocked 9600GSO's that have the external power disabled, anyone know if thats really true
  10. TheMailMan78

    TheMailMan78 Banstick Dummy

    Joined:
    Jun 3, 2007
    Messages:
    20,635 (8.21/day)
    Thanks Received:
    7,244
    Thanks for the info newtek. I've been debating for a while now to get a Physx card and this helps.
  11. ShRoOmAlIsTiC

    ShRoOmAlIsTiC

    Joined:
    Sep 29, 2004
    Messages:
    858 (0.25/day)
    Thanks Received:
    164
    Location:
    Palm Desert, CA


    compairing mine to erocker, I have a gtx260 for physx with a 5850 and get
    Min 46
    Max 128
    avg 87
  12. erocker

    erocker Super Moderator Staff Member

    Joined:
    Jul 19, 2006
    Messages:
    39,137 (13.83/day)
    Thanks Received:
    13,585
    With a single 5850? CrossFire works great with this game.:rolleyes::shadedshu
  13. ShRoOmAlIsTiC

    ShRoOmAlIsTiC

    Joined:
    Sep 29, 2004
    Messages:
    858 (0.25/day)
    Thanks Received:
    164
    Location:
    Palm Desert, CA
    my bad I forgot you had crossfire. Anychance you could retest it with crossfire off?
  14. erocker

    erocker Super Moderator Staff Member

    Joined:
    Jul 19, 2006
    Messages:
    39,137 (13.83/day)
    Thanks Received:
    13,585
    CrossFire off I lose 5 fps avg. The PPU maxes out at 65%. This is one of those games that I don't expect CF to work very well anyways. But what is strange is when the bench is running with CrossFire it seems to go faster. Meh.
  15. newtekie1

    newtekie1 Semi-Retired Folder

    Joined:
    Nov 22, 2005
    Messages:
    19,484 (6.35/day)
    Thanks Received:
    5,725
    I would really think even a 8600GT or 9500GT would be enough, those would be the minimum though(32 Shaders). I think if I was buying today, I'd get a little buffer in cause PhysX gets a little more use, and the minimums go up. I'd say at least something with 48 Shaders(crappy version of the 9600GSO or GT220). Memory bandwidth definitely doesn't matter though, so the $50 8800GT 128-bit newegg has as a shell shocker yesterday would have been killer as a PhysX card.
    Crunching for Team TPU 25 Million points folded for TPU

Currently Active Users Viewing This Thread: 1 (0 members and 1 guest)

Share This Page