BARE FEATS - real world Mac speed tests

PREVIEW: ATI Radeon X850 XT Mac Edition
GeForce 6800 GT Mac Edition

Originally posted June 28th, 2005, by rob-ART morgan, mad scientist
Updated June 29th, 2005, with more accurate test results for the 6800GT.

Apple Online Store has added the ATI Radeon X850 XT as a Configure To Order (CTO) option on new G5 Power Macs. In addition, they have dropped the nVidia GeForce 6800 Ultra and replaced it with the 6800 GT, a slower card. We don't have either of the new cards in the lab right now but we can give you an idea of how they will perform based on past testing of the 6800 GT and an overclocked Radeon X800 XT (that's running at the same speed as the X850 XT).

The Radeon X850 XT is essentially a "speed bumped" Radeon X800 XT (higher core clock and memory clock speeds). Both have 16 pixel pipelines and 6 vertex shaders. It only takes up one slot in the G5 Power Mac. The GeForce 6800 Ultra and GT both take up two slots. The GeForce "siblings" do support up to two 30" Cinema displays. The Radeon X850 XT only supports one.

For most of you, one 30" Cinema would be the most you would ever have -- unless the price drops significantly. So the issue we want to focus on is "Which is faster, the Radeon X850 XT or the GeForce 6800 GT?"

nVidia GeForce 6800 GT
nVidia GeForce 6800 Ultra DDL
Radeon X800 XT Mac Edition
Radeon X850 XT Mac Edition
DVI x 2
DVI x 2
Supports 30" Cinema
Yes (2)
Yes (2)
Yes (1)
Yes (1)
Slots Used
Pixel Fillrate
Pixel Pipelines
Core Clock Speed
Effective Memory Clock Speed
Memory Bandwidth
Transform Rate
Vertex Shader "Engines"
Aftermarket Price
$350-$400 as CTO option or $499 as kit from Apple
No longer offered as CTO option by Apple
$450 from ATI resellers; $499 as a kit from Apple
$350 - $400 CTO option from Apple

Radeon X850 XT* = overclocked Radeon X800 XT using ATIccelerator II to simulate the X850 XT
Radeon X800 XT = ATI Radeon X800 XT Mac Edition (8X, 256MB)
GeForce 6800 Ultra = nVidia GeForce 6800 Ultra DDL (8X, 256MB)
GeForce 6800 GT** = underclocked GeForce 6800 Ultra using
Graphiccelerator to simulate a 6800 GT
All tests were done on a G5/2.5GHz Power Mac with 8MB of memory and Tiger version of OS X (10.4.1).

NOTE: Yesterday, we posted estimates of the 6800 GT's performance, based on past testing in relation to the 6800 Ultra. Today we posted the actual results from a 6800 Ultra "underclocked" to the speeds of the GT. FYI, our estimates yesterday were within tenths of the actual results.

Let's start with some results from a true Tiger Core Image application like iMaginator:

The iMaginator "Test One + Two" refer to test configurations created by Daniel Kottmair for, a German Mac site. He combines various effects and then times how long it takes to playback 200 frames of the resulting morph. We added the results of the two tests together in our graph above.

Motion 2 is a great test of graphic cards since it's one of the few "pro creativity" apps that hand off rendering of filters and effects to the graphics processor. We rendered a RAM Preview of "Fire - Mortise 2 NTSC."

Halo is very OpenGL intensive. Some games are CPU bound. Not Halo:

There is a Halo graph on Apple's site showing the X850 XT and GeForce 6800 GT equal in frame rates, but they were only running Halo at 1024x768. We don't feel that resolution really stresses the graphics cards. That's why we chose to run at 1920x1200, all settings maxed, and FSAA at 4X.

In case you want to try our Halo scenarios, here's the settings we used:
HW Shaders = Advanced Shaders
Detail Objects = On, Model Reflections = On
Lens Flare = High, Model Quality = High
VIDEO: Resolution 1920x1200
Refresh = 0, Framerate Throttle = No Vsync
Specular = On, Shadows = On, Decals = On,
Particles = High, Texture Quality = High
SOUND: Sound Quality = Low, Sound Variety = Low

Doom 3, like Halo, really stresses the graphics card, especially at 1920x1200 and High Quality with dynamic shadows ON:

So which card is best, the Radeon X850 XT or the GeForce 6800 GT? Depends. Depends on what application you want to run fastest. And it depends on whether you are willing to give up two slots to be able to run two 30" Cinema displays or feel one 30" Cinema is all you'll ever need. If I had to pick one, I'd choose the Radeon X850 XT.

The X850 XT has the added advantage of being an ATI product which means it can utilize the ATI Displays utility to override the OpenGL settings in all applications to take advantage of such features as advanced Full Scene Anti-Aliasing and Anisotropic Filtering.

We mentioned earlier that we used ATIccelerator II to overclock the X800 XT core to 500MHz and the memory to 1100MHz, thereby simulating the X850 XT. There is also an application called Graphiccelerator which can be used to overclock a GeForce 6800 GT to run at the same core and memory clock speeds of the 6800 Ultra. At least that's what I'm told by a reader who was successful in doing it.

As indicated earlier, we used Graphiccelerator to underclock our Ultra to run at GT speeds (350MHz core and 500MHz memory) to produce the GT results in the graphs. I suppose we should now try to overclock the Ultra to run at "Extreme" speeds. (He, he, he...)


For your Mac Pro, you have the following 16X PCI Express (PCIe) options:
The GeForce 7300 GT (16X, 256MB, dual-link DVI + single-link DVI port) is the default. We recommend the Radeon X1900 XT (16X, 512MB, two dual-link DVI ports) as a CTO option. It's much faster than the GeForce 7300 GT and just as fast as the expensive Quadro FX 4500. According to Alias/Autodesk, the X1900 XT is the only graphics card without limitations when using Maya 8.5. To custom order your Mac Pro with the Radeon X1900 XT, go to the Apple Store and click on the Mac Pro graphic.

If you didn't order the Radeon X1900 XT with your Mac Pro, you can order the Radeon X1900 XT as an aftermarket kit for your Mac Pro, go to the Apple Store and click on DISPLAYS in the left margin or do a search on "X1900."

NOTE: Mac Pro PCIe graphics cards will not work in Power Mac G5s with PCIe slots -- and vice versa. Nor will Windows PC PCIe graphics cards work in the Mac Pro.

Graphics Card Options for the Dual-Core or Quad-Core G5 with 16X PCI Express slot:
The best option for your Dual-Core or Quad-Core G5 with PCIe slots is the ATI Radeon X1900 G5 Mac Edition released in November 2006. You can buy it directly from ATI's Online Store for $299 (with "trade up" allowance).

It's also sold by Small Dog Electronics and Other World Computing.

The following cards only work on a G5 Power Mac with 8X AGP slot:
The "G5 only" Radeon X800 XT Mac Edition (8X AGP, 256MB, ADC + Dual-Link DVI port) is available from ATI Online Store, Apple's Online Store,, Other World Computing, and Small Dog Electronics. (The MSRP is $299)

Apple's Online Store is no longer selling the GeForce 6800 GT or Ultra, which had Dual-Dual-Link DVI ports (for two 30" Cinemas).

The "G5 only" Radeon 9800 Pro Mac Special Edition (8X AGP, 256MB, ADC + DVI port) is no longer made by ATI.

The following cards work on both the G5 Power Mac (8X AGP) and G4 Power Macs with 2X or 4X AGP:
Other World Computing has the new ATI Radeon 9800 Pro Mac (2X/4X AGP, 256MB, DVI + VGA ports) graphics card in stock for $259. ATI has it on their Online Store for $249. The SKU number is 100-435058, in case you want to make sure you are getting the right card.

ATI Online Store, and Other World Computing have the Radeon 9600 Pro PC and Mac Edition (4X AGP, 256MB, DVI + Dual-Link DVI port) as well. It's compatible with late model G4 Power Macs and all G5 Power Macs with AGP slots. Priced at $199 MSRP it is the lowest priced AGP graphics card with Dual-Link DVI support.

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2005 Rob Art Morgan
"BARE facts on Macintosh speed FEATS"
Email , the webmaster and mad scientist