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Battle for the AGP Throne: GeForce 7800 GS VS. Radeon X850 XT


With the introduction of PCI-Express graphic cards in 2004, 2005 was the takeover year for PCI-Express cards, particularly for high-end graphic cards. 2005 was pretty much void of any high-end AGP card, with the exception of the Radeon X850 XT & Radeon X850 XT PE, which was released in early 2005. While nVIDIA and ATi released their next high-end graphics card for the PCI-Express format last year (the 7800 GTX & X1800 XT respectively), AGP variants of these cards were not released. As a result, most graphic enthusiasts still on AGP took this as a sign that nVIDIA and ATi abandoned the AGP format and switched to PCI-E. It’s no surprise to anyone that the AGP format is being phased out by the newer, faster PCI-Express format, but as The Inquirer has pointed out in one of it’s articles, approximately 55% of the market is still on AGP, so there is still a market for AGP cards. However, after nearly a year without the release of any new AGP cards, nVIDIA finally released the GeForce 6800 GS (based on the NV40 chip) for the AGP a month ago and is set to officially introduce the 7800 GS in early February. As for ATi, some ATi partners have announced their intentions to release X1300 and X1600 variants in AGP format. Indeed, when I found the BFG GeForce 7800 GS OC AGP on the shelf at CompUSA, I also saw a Sapphire X1300 Pro AGP sitting on the shelf as well.

For those that have remained on the AGP format, the only high-end graphic cards available for AGP were the GeForce 6800 GT, GeForce 6800 Ultra, X800 XT/XT PE, and the X850 XT/ XT PE. Those that wanted a faster card than the previously listed cards would have to upgrade their systems to support PCI-Express cards. For some, this meant a total system overhaul would be required, especially for those that have a CPU which does not have a PCI-Express capable motherboard available (i.e. Socket A). Because of this, some have refused to switch to PCI-Express, either due to inconvenience of overhauling an entire system just to use a faster graphics card, or due to a low budget. Now that the GeForce 7800 GS is being released in AGP format, it stands to wonder how this new card will fare against the previous AGP “kings.” To satisfy this curiosity, a Sapphire Radeon X850 XT will be benchmarked against the BFG GeForce 7800 GS OC.

The GeForce 7800 GS:


The GeForce 7800 GS, while not yet formally announced by nVIDIA, can now be found on the shelves of some stores, including CompUSA. The BFG GeForce 7800 GS OC model is currently priced at $349.99 at CompUSA. There is absolutely no official information about this card from nVIDIA’s partners (including BFG) on their website yet, but that is probably because the GeForce 7800 GS AGP is still under NDA, which does not seem to expire until early February.

The GeForce 7800 GS is equipped with a G70 GPU, and while it cannot be confirmed with RivaTuner or other utilities, the GeForce 7800 GS AGP probably has the same number of pixel pipelines and vertex processors found on the 7800 GS PCI-Express card that Anandtech previewed last year in November, which was equipped with 16 pixel pipelines and 6 vertex processors.


The BFG GeForce 7800 GS OC comes in at stock speeds of 400/1250; according to the specifications found on the box, the standard GS speeds appear to be 375/1200. It uses a single-slot cooler and features a single VGA port and a single DVI port. As for power demands of the card, according to the box BFG recommends minimum of a 400W power supply (12V of 20A+). For those that are wondering, the card is indeed using the bridge chip, which is located underneath the heatsink, near the fan assembly. Like it’s older (and faster) GTX and GT brothers, the GS does support several GF7 features, including Gamma and Transparency Anti-Aliasing.

Test System:

Motherboard: DFI NFII Lanparty Ultra B
Processor: Mobile AMD Athlon XP 2600+ @ 2562 MHz
Socket: Socket 462 (Socket A)
Front Side Bus (FSB): 205 MHz
Memory: 2 x Patriot PDC2G3200LL PC3200 1 GB (2.5-3-3-11)
Graphic Cards (AGP):
BFG GeForce 7800 GS OC AGP8X (400/1250)
Sapphire Radeon X850 XT AGP8X (520/540)
Driver Version:
nVIDIA Forceware 83.40
ATi Catalyst 5.13

To test the two AGP cards, an Socket A AGP system was used, equipped with a Mobile Athlon XP 2600+ CPU overclocked to 2562 MHz with a multiplier of 12.5. While an overclocked Mobile Athlon XP is no Athlon 64, it can still provide good gaming performance.


Since there are those that would like to see how well these cards perform when overclocked, the Radeon X850 XT and GeForce 7800 GS were both tested to determine the maximum stable overclocked core and memory speeds.

The Radeon X850 XT card that I have in possession seemed to be a poor overclocker on the core, as the core speed could only handle 526 MHz stable. Any higher speeds would result in the display of small artifacting or even system freezes. Even equipping it with a Zalman VF-700 Cu did not help; it seems the core on this X850 XT is volt-limited. As for the memory, it was a different story, as it was able to overclock as high as 600 MHz and run stable at that speed.

Before overclocking the 7800 GS, I attempted to install RivaTuner RC 15.8 to see the number pipes and vertexes on the 7800 GS, as well as seeing if it was possible to unlock any pixel pipes and vertexes that are locked on this G70 variant. Unfortunately, RivaTuner reported that there was “no information available” about this card, so it is obvious that RivaTuner does not support the 7800 GS AGP (yet). We will have to wait for a future revision of RivaTuner that supports the 7800 GS AGP (or another utility) to determine if this is possible. However, I suspect that nVIDIA has disabled the 8 pipes in hardware, like the 7800 GT.

To overclock the 7800 GS, I used the driver built-in Coolbits 2. Using the “Detect Optimal Frequency” option, it detected a speed of 455 MHz on the core and 1350 MHz on the memory. However, from previous experience with overclocking via Coolbits 2, the detected speeds can usually be a little conservative, so I attempted to overclock the card even further. I was able to reach speeds as high as 500/1390 without Coolbits 2 complaining of instability. In most games and all of the 3DMark applications, I did not find any graphic anomalies or hitching at these speeds, even with long gameplay. However, upon playing Half-Life 2: Lost Coast, I did notice some minor graphic anomalies on some of the rocks, as well as some hitching, so I backed the speed down on both the core and the memory. I was able to settle on 480/1380, speeds which seemed to be free of any graphic anomalies/hitching in all of the games and benchmarks I tested, including Half-Life 2: Lost Coast.

To those who are planning on attaching a Zalman VF-700 Cu to a GeForce 7800 GS AGP, it will not work, at least not without some modding. In my efforts to improve overclocking results on the GeForce 7800 GS, I removed the original BFG heatsink and attempted to install the VF-700 Cu heatsink onto the GeForce 7800 GS, only to discover that the mounting holes on the VF-700 Cu heatsink bracket do not match up to the mounting holes on the board. However, there is enough clearance space for the heatsink to actually fit; perhaps if one modded the bracket, the VF-700 Cu should be attachable to the GeForce 7800 AGP.

Performance Results:

As I have not had enough time to benchmark the two cards, only a few benchmarks and games were tested. At request, I can benchmark some other games at specified settings, including Far Cry, Half-Life 2, Quake IV, Guild Wars, when time forbidding.

3DMark 03:


While Futuremark’s 3DMark 03 benchmark program is now considered a little bit out of date, it is still useful to use, as it tests a graphics card’s ability to render a DirectX 7, 8, and 9 scenes in a single benchmark. At stock speeds, both the GeForce 7800 GS and Radeon X850 XT receive similar scores. The overclocked GeForce 7800 GS takes off in this benchmark, getting around 1700 more 3DMarks more than at it was running at stock speed. It should be interesting to note that in the Direct X 9 GT4 test, the Radeon X850 XT (stock and overclocked) is a bit higher than the GeForce 7800 GS (stock). Even the highly overclocked GeForce 7800 GS barely beats the overclocked Radeon X850 XT in this particular test.

For those that are interested, the Mobile AMD Athlon XP 2600+ at 2562 MHz received CPU scores between 734-738 in these benchmarks.

3DMark 05:


3DMark 05 is a pure DirectX 9 benchmark program, in which only DirectX 9 capable graphic cards are able complete the benchmark. In this test, the GeForce 7800 GS (stock) generally performs slightly lower than the Radeon X850 XT at stock speeds. While the overclocked GeForce 7800 GS is able to outperform the Radeon X850 XT, even with it’s high clocks it cannot reach the 7,000-8,000 range, in which the GeForce 7800 GT and GTX typically perform (at stock speeds) in this benchmark program.

The Mobile AMD Athlon XP 2600+ at 2562 MHz received CPU scores between 3212-3353 in 3DMark 05.

3DMark 06:


3DMark 06, like it’s predecessor, benchmarks a graphic card’s ability to render DirectX 9 scenes, but now takes into account of SM 3.0 and HDR effects, as well as the CPU score, into it’s total 3DMark score. It is also much more demanding on a graphics card than the previous version. Because the Radeon X850 XT is not an SM 3.0 graphic card (it is SM 2.0b) and cannot render the HDR method that 3DMark 06 uses, it cannot complete those tests. Therefore, the SM 2.0 tests should be taken seriously, while the other test results are posted for those that wish to see how the GeForce 7800 GS performs in the SM 3.0 and HDR tests.

With that being said, the FPS in every single test is extremely low in every test. From the SM 2.0 results above, the GeForce 7800 GS at stock speeds slightly outperforms the Radeon X850 XT (overclocked), but not by much. The overclocked GeForce 7800 GS is marginally faster, but still very slow in these tests. The CPU tests are even worse; not even 1 FPS!

Doom 3:

Graphics Mode: High


Doom 3 is an older game programmed in OpenGL. nVIDIA graphic cards have traditionally performed better than ATi graphic cards in OpenGL games like Doom 3 and Quake IV (with exception of the recently launched Radeon X1800/X1900 series), so it is no surprise that the GeForce 7800 GS (stock and overclocked speeds) beats the Radeon X850 XT in this benchmark, even when overclocked. Will the situation change when AA is applied?


The answer is no. While the Radeon X850 XT (overclocked) manages to get close to the GeForce 7800 GS at stock speeds, it just cannot touch the overclocked GeForce 7800 GS.



F.E.A.R. is particularly a very GPU intensive game and has been known to even bog down some high-end PCI-Express systems. In this benchmark, the GeForce 7800 GS at stock speeds seem to equalize with the Radeon X850 XT at overclocked speeds. When the GeForce 7800 GS is overclocked to 480/1380, it is marginally faster than both the GeForce 7800 GS (stock) and Radeon X850 XT (overclocked).


From these benchmarks, the GeForce 7800 GS at stock speeds performs close to a Radeon X850 XT, usually being slightly faster in some tests, and slightly slower in others. It is only when the 7800 GS is overclocked where the performance is a bit better than the X850 XT. I am still hoping that a future revision of RivaTuner or some other pipe unlocking utility will be able to unlock the disabled pipes on a 7800 GS AGP, but I am somewhat wary of that being possible, considering that there have been no successful reports of unlocking pipes on a 7800 GT, so the same may hold true for a 7800 GS.

I will try to post some more benchmarks between the two cards when I have more time to spare.

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