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An underperforming 7800GT

Hey everyone,
Have a bit of a head-scratcher here. I recently picked up a cheap PM G5. It's a dual core 2.3 GHz with the Apple OEM 7800GT video board. The machine is super stable, and if anything, is a bit of an overachiever in pure CPU benchmarks. However, I can't help but feel something is up with the GPU.

First, GUI animations occasionally get a little choppy. For the most part it's fine, but every once in a while (particularly if I've had several windows open at once) they'll all get a bit jittery. And scrolling in the Aquafox browser is consistently slow, at around 10 fps.

These performance issues led me to the OpenMark benchmark, which scored 9331. I can't help but feel that's terribly low! My 1.25GHz MDD with a PC-sourced Radeon 9800 Pro actually beats it, hitting ~9500!

Unreal Tournament 2004 is also not performing as well as it should on a machine of this caliber. It averages around 80 fps, but heavy action can cause the frame rate to dip into the low 40s. I have a Pentium 4 (3.4GHz) with a generation-older 6800GT that, with the same in-game graphics settings, averages around 95-100 fps and dips into the upper-50s when things get hectic. The Doom 3 timedemo? Around 71 fps on the G5; 82 on the P4. Granted, the PC runs XP, but a dual core G5 with a newer video board should run rings around any P4, right?

The power cable is plugged into the card, and I've made sure that the CPU is in high performance mode. I also tried Sorbet Leopard after hearing that it's generally a bit speedier than Stock Leopard. However, a clean install of Sorbet yielded...exactly 9331! Weird that this benchmark is so freakishly consistent on this machine--even across different OS versions! Almost seems like it's running into an artificial limit somewhere. Normally I'd blame such behaviour on Vsync, but the benchmark does start at over 2000 fps.

Could this be a driver issue? I've noticed that the GPU fan doesn't slow down when the desktop appears, it just remains at full-blast all the time. Going back to my P4/6800GT machine again, that system screams like a banshee during POST, but becomes almost inaudible when the video driver kicks in & the Welcome screen appears.

Are there alternative Nvidia drivers for the Mac? Any suggestions would be appreciated!
 
I don't know about alternate Nvidia drivers.

I've made a ROM to make the card usable in the oldest PCI Power Macs with a PCIe adapter (acceleration only for Mac OS X). Tested successfully in a Beige G3 and B&W G3. A Quadro FX 4500 was successful in a Power Mac 9600.

My Quad G5 gets:
9331 OpenMark Leopard Quad G5 7800GT 1920x1200 (same as yours)
9331 OpenMark Leopard Quad G5 7800GT 2560x1600 (same as yours)
9124 OpenMark Leopard Quad G5 7800GT 3840x2160 (one step lower)

OpenMark for B&W G3 gets 7746 (2560x1440 32bpp) 7372 (1920x1080x32bpp)
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-33188527
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-33312784
OpenMark for my Quad G5:
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-31729215

Other OpenMark benchmarks:
https://forums.macrumors.com/thread...l-work-in-a-beige-power-macintosh-g3.2303689/
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/post-20773020 (same as yours)
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/post-20831943 (not same as yours 1680x1050)
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/post-21695959 (strange results)

The score appears to be related to the max number of triangles when the framerate drops to below 10 fps.
Here's a list of possible number of triangles values which accounts for the consistency of results:
Code:
....
8719488
8921088 <- Leopard Quad G5 7800 GT 3840x2160 (9 fps) so the score is the next number of triangles ÷ 10000 = 9124
9124992 <- Leopard Quad G5 7800 GT 1920x1200 (9 fps) so the score is the next number of triangles ÷ 10000 = 9331
9331200
9539712
9750528
...
12460032 <- Surrat's result (1680x1050) = 12700
12700800
...
18580608 <- Quad G5 7800 GTX 2560x1600 (9fps) so the score is the next number of triangles ÷ 10000 = 18874
18874####
...

7800 GTX can do almost exactly twice as many triangles.

Maybe 9331 is a cap for lower resolutions?
Maybe retest with the lowest resolution? 640x480? 1680x1050?
Maybe should retest in Tiger?
Test if you can do more than 9331200 triangle. What's the FPS?
What's the max number of triangles before reaching 5 fps?
 
Really unusual, you've done some thorough testing, OpenMark seems to have hit a wall. I don't think there were any better third-party drivers under OS X for nVidia cards, and they are terribly unoptimised with little comparison for gaming FPS compared to Windows drivers.

See here for example which in gaming shows the G5 to be trounced by a lowly Athlon and P4. The G5 will shine in anything else.


As for the stuttering, try adjust refresh rates, check CPU temps if any overheating.
 
I don't know about alternate Nvidia drivers.

I've made a ROM to make the card usable in the oldest PCI Power Macs with a PCIe adapter (acceleration only for Mac OS X). Tested successfully in a Beige G3 and B&W G3. A Quadro FX 4500 was successful in a Power Mac 9600.

My Quad G5 gets:
9331 OpenMark Leopard Quad G5 7800GT 1920x1200 (same as yours)
9331 OpenMark Leopard Quad G5 7800GT 2560x1600 (same as yours)
9124 OpenMark Leopard Quad G5 7800GT 3840x2160 (one step lower)

OpenMark for B&W G3 gets 7746 (2560x1440 32bpp) 7372 (1920x1080x32bpp)
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-33188527
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-33312784
OpenMark for my Quad G5:
https://forums.macrumors.com/thread...eige-power-macintosh-g3.2303689/post-31729215

Other OpenMark benchmarks:
https://forums.macrumors.com/thread...l-work-in-a-beige-power-macintosh-g3.2303689/
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/post-20773020 (same as yours)
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/post-20831943 (not same as yours 1680x1050)
https://forums.macrumors.com/threads/some-ppc-openmark-benchmarks.1848060/post-21695959 (strange results)

The score appears to be related to the max number of triangles when the framerate drops to below 10 fps.
Here's a list of possible number of triangles values which accounts for the consistency of results:
Code:
....
8719488
8921088 <- Leopard Quad G5 7800 GT 3840x2160 (9 fps) so the score is the next number of triangles ÷ 10000 = 9124
9124992 <- Leopard Quad G5 7800 GT 1920x1200 (9 fps) so the score is the next number of triangles ÷ 10000 = 9331
9331200
9539712
9750528
...
12460032 <- Surrat's result (1680x1050) = 12700
12700800
...
18580608 <- Quad G5 7800 GTX 2560x1600 (9fps) so the score is the next number of triangles ÷ 10000 = 18874
18874####
...

7800 GTX can do almost exactly twice as many triangles.
Oh wow, lots of info there! Thanks a bunch for the links! Interesting that several others are getting the same 9331 score with a 7800GT as well. I tested OpenMark at 1024x768 (down from 1920x1200) and got the same score, so...CPU limit?
But no, that makes no sense, since my G4 1.25 w/ Radeon 9800 Pro outpaces it. That machine is running Tiger though, sooo:
Maybe should retest in Tiger?
Guess I'll try that next!
Test if you can do more than 9331200 triangle. What's the FPS?
What's the max number of triangles before reaching 5 fps?
I don't believe there's a way to really customize the benchmark? Unless I'm missing something really obvious here.

Really unusual, you've done some thorough testing, OpenMark seems to have hit a wall. I don't think there were any better third-party drivers under OS X for nVidia cards, and they are terribly unoptimised with little comparison for gaming FPS compared to Windows drivers.

See here for example which in gaming shows the G5 to be trounced by a lowly Athlon and P4. The G5 will shine in anything else.


As for the stuttering, try adjust refresh rates, check CPU temps if any overheating.
Terribly unoptimized indeed! Guess there really was no need to go much beyond a 6800GT/X800 class card even on the late-model G5s, unless some pro-level apps were able to take better advantage of them than games could.
Refresh rate's at 60; boring old office LCD here. CPU temperature during a stress test peaks at 61 C.
 
I don't believe there's a way to really customize the benchmark? Unless I'm missing something really obvious here.
When it's not running the benchmark, I think you can change the image with the mouse or keyboard or something.
It says:
Code:
#### triangles (MouseWheel to change)
### FPS
so try the mouse wheel.
 
Test if you can do more than 9331200 triangle. What's the FPS?
What's the max number of triangles before reaching 5 fps?
At 9539712 triangles, 9 FPS.
Max number of triangles before dropping to 5 FPS is 15769728. It drops to 5 at 16313472.

But you know what? It was Leopard all along! I installed Tiger and the score ballooned to 14450. Generally, OS animation in Tiger when there are a lot of open windows is smoother as well. I also noticed right off the bat that the fan immediately dropped to idle speed when the desktop loaded in--this is exactly what my P4/6800GT/WinXP machine does as well. See, I knew it was driver-related, I knew it! :)

So I guess the Leopard 7800GT driver is just kind of broken, or an afterthought at the very least. Assuming that by 2007, the primary focus at Apple was on Intel.

Is there a way to rip the NV GPU driver out of Tiger and use it in Leopard, or are the driver models too different? I'd definitely prefer to use (Sorbet) Leopard, if I could do so without massively throttling the GPU.
 
Nice find, are games better in FPS too? I’m sure you could inject the Tiger nVidia kexts into Leopard, see OSX86 forums.
 
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