Preface: Although there have been vast comparisons between X1900XT and 7900GT offerings, most of them have involved just plain performance numbers without much insight into image quality, which can be equally important. This brief post does not attempt to corral the endless number of configurations on overclocks and image options that are available for both solutions, but rather attempt to classify the performance from a visual standpoint in terms of framerates and quality with the more simplistic and achievable clocks and settings. Where there are gaps, as I'm sure there will be, I will do what I can to fill them in, but I too am bandwidth limited (Real life with work and a girlfriend who hates computers cannot readily be overcome with MHz! ). I'd like to thank Elfear for his contributions to this article and helping me on the ATI front.
Quantitative and qualitative comparison of overclocked ATi X1900XT and nVidia 7900GT
Part I - Oblivion performance and IQ benchmarks
Much has been made by ATI's excellent ATI X1900XT VPU
( http://www.anandtech.com/video/showdoc.aspx?i=2679 ) and for good reasons. With it's 625MHz stock core clock speeds, GDDR3 memory running at an aggregate 1450MHz data rate, and staggering 48 pixel shader architecture, not too mention very competitive pricing in the low $425 range, it has gone on to take the performance / value crown in the present day video arena. Combine this with folks readily achieving X1900XTX clocks or well beyond ( http://www.ocforums.com/showthread.php?t=440151 ), it is a monster of a card for fair entry price!
While the affordable $300 7900GT has been a hot selling commodity, its stock performance has been lackluster compared to ATI's X1xxx line of graphic cards. Spotting 175 MHz core clock speeds, as well 100 MHz memory clocks and 24 pixel shaders to its Canadian competitor in "base" form; the little NVIDIA champ doesn't bring much punch to the battle. But just like David vs. Goliath, fortunately its new 90nm GPU process brings forth a slingshot of an overclock to the table to try to topple its heavily favored arch-rival. The 7900GT volt mod ( http://forums.anandtech.com/messageview...atid=31&threadid=1847758&enterthread=y ) has brought a lot of controversy to the community in its simplicity as well as performance to this once mediocre platform; rather than ATIs more user friendly software adjustable voltage modifications, it require a hard (semi-permanent) solution via a conductive ink pen in order to achieve the same voltage affects. Although the long term affects of both overvoltage solutions remains to be seen in terms of reliability ,quite a few folks have tried and had much success with this 7900GT volt mod already (
http://www.xtremesystems.org/forums/showthread.php?t=92874 ). Make no mistake about it, not since the recent trends of AMD Opteron 165 CPUs overclocking to absurd frequencies have we seen such a performance delta between stock and modified.
In the first round of comparisons, we attempt to take a look at both platforms from a quantitative (performance) as well as qualitative (image quality) perspective under Oblivion, the hottest game to date. Sporting a software engine that has support for SM3.0 HDR affects, as well as immense shadow and texturing, it has really put a heavy emphasis on GPU performance. Two particularly benchmark methodologies will be
utilized:
1) First, stressing GPU raw horsepower, 2 sets of gameplay in a ~10 minute outdoor trek and ~5 minute run in an actual Oblivion Gate dungeon gameplay will both be FRAPed for framerates comparisons
2) Secondarily, an image quality shot will be made on the different platforms at a set point with different image quality settings in anti-aliasing, antistrophic filters, etc.
All setting will be performed at 1920x1080 resolutions for the time being, as it is the native resolution of my monitor. Note: Because I am doing the frapping in actual gameplay, there will be some variances in the tests. I would imagine a margin of error of ~5% for the scores due to the random nature executing each run in a real live game environment. This philosophy in testing follows Anandtech's own GPU comparion in Oblivion ( http://www.anandtech.com/video/showdoc.aspx?i=2746 ). Many of the tests were double, even triple checked to ensure accuracy. What should matter most to folks is the not necessarily the maximum framerate, but rather the average, and to some certain extent, the minium, as it will be more indicative of actual gameplay.
The 7900GT was first run with the "soft" auto overclock settings of 520MHz and 720 MHz respectively via Coolbits for comparison purposes. It was then volt-modded to 1.4V and again auto overclock set to 675 MHz Core and 875MHz Memory clocks with Coolbits and Powerstrip utility. Note: this was using an aftermarket Artic Cooling NV Silencer 5 (which most former 7800GT/GTX owners that upgraded already have) which is desirable for maximum overclocks. The stock "base" 7900GT HSF is small, somewhat noisy with its whiny fans, and does not cover the memory chips sufficiently. If you have the "factory overclocked" versions, thes have a better copper base, more quiet solutions, that also cover the memory areas.
The ATI X1900XT was overclocked via Catalyst Control Center's Overdrive utility automatically to the maximum of 655MHz Core and 792 MHz Memory clock too; not too shabby since it was beyond X1900XTX specifications. Note: further overclocking tools such as ATI Tools ( http://www.techpowerup.com/atitool/ ) would allow you to overclock even more by tweaking the clocks and voltages independent of the CCC controls. For this particular benchmark, I settled on the Overdrive derived overclocks as higher settings exhibited instability issues on my particular card. It is not my intention to portray the x1900xt as having a low overclock boundary but I am time and resource constrained putting all the comparisons together. In fact many people have achieved much greater overclocks on the platform as well! Note: I only utilized the stock HSF on the X1900XT as it is a rather beefy unit and is actually pretty quiet....when not utilized at full GPU capcity for an extensive amount of time though. BUT, when gameplay gets heavy and the card has been heat soaked in sufficiently, the blower emits a rather annoying moan at its higher settings akin to a leafblower, and gets rather HOT. I did not have an aftermarket HSF available, but there are very quiet solutions such as Artic Cooling's Accelero line that may also achieve better overclocks, although again many have achieve 700+MHz on the stock cooler.
System Setup:
Asus A8N32-SLI motherboard
AMD Opteron 165 @ 3.0GHz (Dual Core hotfix enabled)
2GB Corsair XMS 3200 2.5-3-3-6 @ 214MHz
Hitachi 500GB x 3 (RAID 0) SATA2
Windows XP Pro SP2
Asus 7900GT w/ NVIDIA 84.43 Drivers
ATI Radeon X1900XT w/ Catalyst 6.4 + 6.3 w/ "Chuck" patch
Oblivion Settings: All high settings (100% or quality enabled)
Test 1: Performance testing under usual gameplay
Run A (Outdoor Areas): Testing methodology will consist of having the main character ride around the outer road of the Imperial City all the way around to the southern bridge. This horse ride will go through heavy forest and grass areas, as well as by at least one Oblivion gate and several enemy characters. When the character arrives at the end bridge, he will fight from 1-3 foes including the highwayman on the bridge. Once completed the FRAP run will be stopped.
HDR w/ No AA or No AF - Performance setting:
ATI Stock 621MHz Core - 720MHz Mem
Frames, Time (ms), Min, Max, Avg
14599, 523496, 18, 66, 27.888
ATI OC 655MHz Core - 792MHz Mem
Frames, Time (ms), Min, Max, Avg
16561, 551838, 11, 63, 30.011
ATI OC 692MHz Core - 842MHz Mem (Soft Volt Moded)
Frames, Time (ms), Min, Max, Avg
16675, 522249, 12, 57, 31.929
NV 7900GT Stock OC 520MHz Core - 720MHz Mem
Frames, Time (ms), Min, Max, Avg
13144, 554991, 1, 46, 23.683
NV 7900GT VM OC 675MHz Core - 875MHz Mem
Frames, Time (ms), Min, Max, Avg
17245, 571843, 9, 60, 30.157
Assessment: With just HDR turned on in their respective performance quality settings, the overclocked x1900XT and 7900GT come to almost a dead heat in terms of framerates. You'll note how the stock OC 7900GT lags behind, but still has a somewhat respectable and playable avg. framerates. Even at stock settings, the X1900XT is still a good performer at such high resolutions!
HDR w/ No AA 8x AF (
ATI Stock 621MHz Core - 720MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
13968, 543034, 2, 57, 25.722
ATI OC 655MHz Core - 792MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
14778, 540610, 16, 58, 27.336
ATI OC 655MHz Core - 792MHz Mem (Standard AF)
Frames, Time (ms), Min, Max, Avg
14013, 501019, 13, 56, 27.969
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Performance)
Frames, Time (ms), Min, Max, Avg
15783, 547224, 0, 58, 28.842
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Quality)
Frames, Time (ms), Min, Max, Avg
13458, 529921, 9, 50, 25.396
NV 7900GT VM OC 675MHz Core - 875MHz Mem (High Quality)
Frames, Time (ms), Min, Max, Avg
11625, 530061, 2, 43, 21.931
Assessment: Although the volt modded 7900GT OC barely leads, you will note that I am utilizing ATI's High Quality Antistrophic Filtering which is a much better AF solution than NVIDIA?s. In fact, I found some IQ quirks with 8X AF enabled on the 7900GT (see Image Quality section for more details) that could only be minimized, and not eliminated when set to the Quality setting for NVIDIA. Doing this also cuts down on the average frame rate of the 7900GT below that of the X1900XT, especially with the High Quality setting. Seems strange since at best there seems to be only some minute differences in image quality from the 2 settings from what I can discern. I also tried with 4X HQAF settings on the X1900XT and there was no appreciable framerate loss between 4X and 8X HQAF modes, thus settled on 8X AF from here on. There seemed to be no discernable performance hit enabling HQ AF either.[/i]
HDR-4X AA 8x HQAF
ATI Stock 621MHz Core - 720MHz Mem
Frames, Time (ms), Min, Max, Avg
10539, 562581, 0, 36, 18.733
ATI OC 655MHz Core - 792MHz Mem
Frames, Time (ms), Min, Max, Avg
11492, 549567, 12, 45, 20.911
Assessment: One of the unique features of the X1000 line of ATI gpu's is the ability to do BOTH HDR and AA concurrently with the infamous "Chuck" patch that is unfortunately unsupported by both Bethesda Softworks and ATI, officially. As you can see above, it does incur a hit to framerates since the outdoors environment is loaded with textures, but playrate is still at a respectable ~21/19 FPS rate for the X1900XT. The only way to enable AF and AA concurrently on the 7900GT is to go to the older SM2.0 Bloom features, which is not as realistic (see pictures in Image Quality section below). I must note, at the higher resolutions like 1920x1080, even at 4X AA, it is not readily discernable with anti-aliasing on or off. But at lower resolutions like 1280x1020, it is almost a must with the complex and acute sceneries that Oblivion generates (see pictures in Image Quality section below).
Run B (Dungeon Areas): Testing methodology will consist of having the main character run and fight through the first Oblivion Gate dungeon area in Kvetch. Once the Sigil Stone is captured, the FRAP run will be stopped.
HDR-No AA 8x AF - OG
ATI Stock 621MHz Core - 720MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
3260, 91669, 7, 73, 35.563
ATI OC 655MHz Core - 792MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
4002, 99704, 17, 83, 40.139
ATI OC 655MHz Core - 792MHz Mem (Standard AF)
Frames, Time (ms), Min, Max, Avg
3652, 91289, 17, 85, 40.005
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Performance)
Frames, Time (ms), Min, Max, Avg
4028, 95370, 18, 77, 42.236
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Quality)
Frames, Time (ms), Min, Max, Avg
3865, 96102, 18, 71, 40.218
NV 7900GT VM OC 675MHz Core - 875MHz Mem (High Quality)
Frames, Time (ms), Min, Max, Avg
3697, 92707, 18, 70, 39.878
Assessment: Surprisingly, the volt modded overclocked 7900GTs actually take the crown when visual quality is not a concern. Again, it does take a framerate hit when the image quality is turned up. But the hit to High Quality setting isn't as apparent as in the outdoors and is almost neglible considering the margin of error strangely enough. The X1900XT scores are very good, especially in light of the fact HQ 8X AF is enabled. There seemed to be no discernable performance hit enabling HQ AF either.
Overall Performance Results
Our little David volt modded and overclocked 7900GT threw a pretty good slingshot at its Goliath competitor keeping up with the X1900XT in the two comparison Oblivion Outdoors and Dungeon runs. But while it was aiming for the X1900XTs head, it merely gave it a sucker punch shot in the gut, as it took an appreciable framerate hit with the image quality settings turned on to mimic ATI's excellent HQ 8X AF solution. Still it's not bad considering where its anemic stock performance is at, and with the affordable entry pricepoint, it's no wonder a top seller! As for the X1900XT, it IS ALL that and a can of worms: performance w/ great image quality to boot. Make no mistake about it, ATI does have a monster on their hands, with nVidia now having to play catch up to slay the red beast!
Addendum: I was finally able to overclock beyond the ATI Overdrive derived settings using ATI Tools. I had experienced frequent instability before; typically running OK on an overclock then crashing the system suddenly. But I finally found the culprit: an insufficient power supply! Although my trusty Silverstone 460W unit seemed capable never once flinching on the 7900GT even volt modded and overclocked, I noticed that during artifact testing with the ATI overclocks my 12V line would dip +250mV. Luckily for me, my local electronics store had a great deal on a Silverstone 600W modular power supply which I already picked up and had yet to install. After rectifying this, I was finally able to achieve a stable 692 Core / 842 Memory overclock, which I added in the initial RUN A results as a reference for everyone. With the immense power draw of the stock X1900XT, ATI does stipulate a minimum of 450W power supply, so with a 3.0GHz Dual Core Opteron CPU, 3 SATA HDDs, and the rest of my system running concurrently, I fathom I taxed out my old power supply. While this may be an isolated incident due to my system configuration, a word of caution goes out for those planning for even higher overclocks on the ATI platform; this baby is a powerful Chihuahua but sure guzzles electrons like a grown Doberman.
Quantitative and qualitative comparison of overclocked ATi X1900XT and nVidia 7900GT
Part I - Oblivion performance and IQ benchmarks
Much has been made by ATI's excellent ATI X1900XT VPU
( http://www.anandtech.com/video/showdoc.aspx?i=2679 ) and for good reasons. With it's 625MHz stock core clock speeds, GDDR3 memory running at an aggregate 1450MHz data rate, and staggering 48 pixel shader architecture, not too mention very competitive pricing in the low $425 range, it has gone on to take the performance / value crown in the present day video arena. Combine this with folks readily achieving X1900XTX clocks or well beyond ( http://www.ocforums.com/showthread.php?t=440151 ), it is a monster of a card for fair entry price!
While the affordable $300 7900GT has been a hot selling commodity, its stock performance has been lackluster compared to ATI's X1xxx line of graphic cards. Spotting 175 MHz core clock speeds, as well 100 MHz memory clocks and 24 pixel shaders to its Canadian competitor in "base" form; the little NVIDIA champ doesn't bring much punch to the battle. But just like David vs. Goliath, fortunately its new 90nm GPU process brings forth a slingshot of an overclock to the table to try to topple its heavily favored arch-rival. The 7900GT volt mod ( http://forums.anandtech.com/messageview...atid=31&threadid=1847758&enterthread=y ) has brought a lot of controversy to the community in its simplicity as well as performance to this once mediocre platform; rather than ATIs more user friendly software adjustable voltage modifications, it require a hard (semi-permanent) solution via a conductive ink pen in order to achieve the same voltage affects. Although the long term affects of both overvoltage solutions remains to be seen in terms of reliability ,quite a few folks have tried and had much success with this 7900GT volt mod already (
http://www.xtremesystems.org/forums/showthread.php?t=92874 ). Make no mistake about it, not since the recent trends of AMD Opteron 165 CPUs overclocking to absurd frequencies have we seen such a performance delta between stock and modified.
In the first round of comparisons, we attempt to take a look at both platforms from a quantitative (performance) as well as qualitative (image quality) perspective under Oblivion, the hottest game to date. Sporting a software engine that has support for SM3.0 HDR affects, as well as immense shadow and texturing, it has really put a heavy emphasis on GPU performance. Two particularly benchmark methodologies will be
utilized:
1) First, stressing GPU raw horsepower, 2 sets of gameplay in a ~10 minute outdoor trek and ~5 minute run in an actual Oblivion Gate dungeon gameplay will both be FRAPed for framerates comparisons
2) Secondarily, an image quality shot will be made on the different platforms at a set point with different image quality settings in anti-aliasing, antistrophic filters, etc.
All setting will be performed at 1920x1080 resolutions for the time being, as it is the native resolution of my monitor. Note: Because I am doing the frapping in actual gameplay, there will be some variances in the tests. I would imagine a margin of error of ~5% for the scores due to the random nature executing each run in a real live game environment. This philosophy in testing follows Anandtech's own GPU comparion in Oblivion ( http://www.anandtech.com/video/showdoc.aspx?i=2746 ). Many of the tests were double, even triple checked to ensure accuracy. What should matter most to folks is the not necessarily the maximum framerate, but rather the average, and to some certain extent, the minium, as it will be more indicative of actual gameplay.
The 7900GT was first run with the "soft" auto overclock settings of 520MHz and 720 MHz respectively via Coolbits for comparison purposes. It was then volt-modded to 1.4V and again auto overclock set to 675 MHz Core and 875MHz Memory clocks with Coolbits and Powerstrip utility. Note: this was using an aftermarket Artic Cooling NV Silencer 5 (which most former 7800GT/GTX owners that upgraded already have) which is desirable for maximum overclocks. The stock "base" 7900GT HSF is small, somewhat noisy with its whiny fans, and does not cover the memory chips sufficiently. If you have the "factory overclocked" versions, thes have a better copper base, more quiet solutions, that also cover the memory areas.
The ATI X1900XT was overclocked via Catalyst Control Center's Overdrive utility automatically to the maximum of 655MHz Core and 792 MHz Memory clock too; not too shabby since it was beyond X1900XTX specifications. Note: further overclocking tools such as ATI Tools ( http://www.techpowerup.com/atitool/ ) would allow you to overclock even more by tweaking the clocks and voltages independent of the CCC controls. For this particular benchmark, I settled on the Overdrive derived overclocks as higher settings exhibited instability issues on my particular card. It is not my intention to portray the x1900xt as having a low overclock boundary but I am time and resource constrained putting all the comparisons together. In fact many people have achieved much greater overclocks on the platform as well! Note: I only utilized the stock HSF on the X1900XT as it is a rather beefy unit and is actually pretty quiet....when not utilized at full GPU capcity for an extensive amount of time though. BUT, when gameplay gets heavy and the card has been heat soaked in sufficiently, the blower emits a rather annoying moan at its higher settings akin to a leafblower, and gets rather HOT. I did not have an aftermarket HSF available, but there are very quiet solutions such as Artic Cooling's Accelero line that may also achieve better overclocks, although again many have achieve 700+MHz on the stock cooler.
System Setup:
Asus A8N32-SLI motherboard
AMD Opteron 165 @ 3.0GHz (Dual Core hotfix enabled)
2GB Corsair XMS 3200 2.5-3-3-6 @ 214MHz
Hitachi 500GB x 3 (RAID 0) SATA2
Windows XP Pro SP2
Asus 7900GT w/ NVIDIA 84.43 Drivers
ATI Radeon X1900XT w/ Catalyst 6.4 + 6.3 w/ "Chuck" patch
Oblivion Settings: All high settings (100% or quality enabled)
Test 1: Performance testing under usual gameplay
Run A (Outdoor Areas): Testing methodology will consist of having the main character ride around the outer road of the Imperial City all the way around to the southern bridge. This horse ride will go through heavy forest and grass areas, as well as by at least one Oblivion gate and several enemy characters. When the character arrives at the end bridge, he will fight from 1-3 foes including the highwayman on the bridge. Once completed the FRAP run will be stopped.
HDR w/ No AA or No AF - Performance setting:
ATI Stock 621MHz Core - 720MHz Mem
Frames, Time (ms), Min, Max, Avg
14599, 523496, 18, 66, 27.888
ATI OC 655MHz Core - 792MHz Mem
Frames, Time (ms), Min, Max, Avg
16561, 551838, 11, 63, 30.011
ATI OC 692MHz Core - 842MHz Mem (Soft Volt Moded)
Frames, Time (ms), Min, Max, Avg
16675, 522249, 12, 57, 31.929
NV 7900GT Stock OC 520MHz Core - 720MHz Mem
Frames, Time (ms), Min, Max, Avg
13144, 554991, 1, 46, 23.683
NV 7900GT VM OC 675MHz Core - 875MHz Mem
Frames, Time (ms), Min, Max, Avg
17245, 571843, 9, 60, 30.157
Assessment: With just HDR turned on in their respective performance quality settings, the overclocked x1900XT and 7900GT come to almost a dead heat in terms of framerates. You'll note how the stock OC 7900GT lags behind, but still has a somewhat respectable and playable avg. framerates. Even at stock settings, the X1900XT is still a good performer at such high resolutions!
HDR w/ No AA 8x AF (
ATI Stock 621MHz Core - 720MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
13968, 543034, 2, 57, 25.722
ATI OC 655MHz Core - 792MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
14778, 540610, 16, 58, 27.336
ATI OC 655MHz Core - 792MHz Mem (Standard AF)
Frames, Time (ms), Min, Max, Avg
14013, 501019, 13, 56, 27.969
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Performance)
Frames, Time (ms), Min, Max, Avg
15783, 547224, 0, 58, 28.842
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Quality)
Frames, Time (ms), Min, Max, Avg
13458, 529921, 9, 50, 25.396
NV 7900GT VM OC 675MHz Core - 875MHz Mem (High Quality)
Frames, Time (ms), Min, Max, Avg
11625, 530061, 2, 43, 21.931
Assessment: Although the volt modded 7900GT OC barely leads, you will note that I am utilizing ATI's High Quality Antistrophic Filtering which is a much better AF solution than NVIDIA?s. In fact, I found some IQ quirks with 8X AF enabled on the 7900GT (see Image Quality section for more details) that could only be minimized, and not eliminated when set to the Quality setting for NVIDIA. Doing this also cuts down on the average frame rate of the 7900GT below that of the X1900XT, especially with the High Quality setting. Seems strange since at best there seems to be only some minute differences in image quality from the 2 settings from what I can discern. I also tried with 4X HQAF settings on the X1900XT and there was no appreciable framerate loss between 4X and 8X HQAF modes, thus settled on 8X AF from here on. There seemed to be no discernable performance hit enabling HQ AF either.[/i]
HDR-4X AA 8x HQAF
ATI Stock 621MHz Core - 720MHz Mem
Frames, Time (ms), Min, Max, Avg
10539, 562581, 0, 36, 18.733
ATI OC 655MHz Core - 792MHz Mem
Frames, Time (ms), Min, Max, Avg
11492, 549567, 12, 45, 20.911
Assessment: One of the unique features of the X1000 line of ATI gpu's is the ability to do BOTH HDR and AA concurrently with the infamous "Chuck" patch that is unfortunately unsupported by both Bethesda Softworks and ATI, officially. As you can see above, it does incur a hit to framerates since the outdoors environment is loaded with textures, but playrate is still at a respectable ~21/19 FPS rate for the X1900XT. The only way to enable AF and AA concurrently on the 7900GT is to go to the older SM2.0 Bloom features, which is not as realistic (see pictures in Image Quality section below). I must note, at the higher resolutions like 1920x1080, even at 4X AA, it is not readily discernable with anti-aliasing on or off. But at lower resolutions like 1280x1020, it is almost a must with the complex and acute sceneries that Oblivion generates (see pictures in Image Quality section below).
Run B (Dungeon Areas): Testing methodology will consist of having the main character run and fight through the first Oblivion Gate dungeon area in Kvetch. Once the Sigil Stone is captured, the FRAP run will be stopped.
HDR-No AA 8x AF - OG
ATI Stock 621MHz Core - 720MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
3260, 91669, 7, 73, 35.563
ATI OC 655MHz Core - 792MHz Mem (HQAF)
Frames, Time (ms), Min, Max, Avg
4002, 99704, 17, 83, 40.139
ATI OC 655MHz Core - 792MHz Mem (Standard AF)
Frames, Time (ms), Min, Max, Avg
3652, 91289, 17, 85, 40.005
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Performance)
Frames, Time (ms), Min, Max, Avg
4028, 95370, 18, 77, 42.236
NV 7900GT VM OC 675MHz Core - 875MHz Mem (Quality)
Frames, Time (ms), Min, Max, Avg
3865, 96102, 18, 71, 40.218
NV 7900GT VM OC 675MHz Core - 875MHz Mem (High Quality)
Frames, Time (ms), Min, Max, Avg
3697, 92707, 18, 70, 39.878
Assessment: Surprisingly, the volt modded overclocked 7900GTs actually take the crown when visual quality is not a concern. Again, it does take a framerate hit when the image quality is turned up. But the hit to High Quality setting isn't as apparent as in the outdoors and is almost neglible considering the margin of error strangely enough. The X1900XT scores are very good, especially in light of the fact HQ 8X AF is enabled. There seemed to be no discernable performance hit enabling HQ AF either.
Overall Performance Results
Our little David volt modded and overclocked 7900GT threw a pretty good slingshot at its Goliath competitor keeping up with the X1900XT in the two comparison Oblivion Outdoors and Dungeon runs. But while it was aiming for the X1900XTs head, it merely gave it a sucker punch shot in the gut, as it took an appreciable framerate hit with the image quality settings turned on to mimic ATI's excellent HQ 8X AF solution. Still it's not bad considering where its anemic stock performance is at, and with the affordable entry pricepoint, it's no wonder a top seller! As for the X1900XT, it IS ALL that and a can of worms: performance w/ great image quality to boot. Make no mistake about it, ATI does have a monster on their hands, with nVidia now having to play catch up to slay the red beast!
Addendum: I was finally able to overclock beyond the ATI Overdrive derived settings using ATI Tools. I had experienced frequent instability before; typically running OK on an overclock then crashing the system suddenly. But I finally found the culprit: an insufficient power supply! Although my trusty Silverstone 460W unit seemed capable never once flinching on the 7900GT even volt modded and overclocked, I noticed that during artifact testing with the ATI overclocks my 12V line would dip +250mV. Luckily for me, my local electronics store had a great deal on a Silverstone 600W modular power supply which I already picked up and had yet to install. After rectifying this, I was finally able to achieve a stable 692 Core / 842 Memory overclock, which I added in the initial RUN A results as a reference for everyone. With the immense power draw of the stock X1900XT, ATI does stipulate a minimum of 450W power supply, so with a 3.0GHz Dual Core Opteron CPU, 3 SATA HDDs, and the rest of my system running concurrently, I fathom I taxed out my old power supply. While this may be an isolated incident due to my system configuration, a word of caution goes out for those planning for even higher overclocks on the ATI platform; this baby is a powerful Chihuahua but sure guzzles electrons like a grown Doberman.