XFX 7950 GX2 XXX

 

We invite you to join Scott and I as we explore in detail the inner workings of GeForce 7950 GX2. We consider ourselves extremely fortunate to have garnered XFX’s top of the line “XXX” version of this card which comes from the factory with an default core clock of 570 MHz, and a combined memory clock of 1550 MHz for today’s review.

 

INTRODUCTION

All and all the past year has probably been one of the most technologically significant years in the history of the graphics industry. We realize this is a rather bold statement, but think about it! We’ve seen graphics cards go from a standard of 128 Mb up to 256 Mb and then to a whopping 512 Mb of on-board, super high speed GDDR3 memory. We’ve witnessed the GPU speeds almost double and the quality of their output rise exponentially. We have seen the introduction of both SLI™ and Crossfire™ technologies that support multiple video cards working in unison on the same motherboard. Geez we’re already breathless just thinking about these advancements, but we aren’t finished yet!

Can you believe it? Today again is the day! NVIDIA has had two major launches of totally new products within a two week span! On May 23 they launched their new and innovative NVIDIA 500 series of media and communications processors centered around the also new socket AM2 processors from AMD. Today, just 14 days later, NVIDIA is launching the new Flagship of their graphics processor line, the 7950 GX2. The 7950 GX2 in itself is one of, if not the most highly anticipated products of the year.

What makes this product such a ball buster in theory is plain and simple if you sketch it out on paper. All the 7950 GX2 has to do is combine two extremely high performance GPUs running in total harmony on two conjoined, multi-layered PCB cards with plenty of speed and memory to get the job done better than its predecessors. Oh, and do it without generating so much heat and noise that it melts Bubba’s new aluminum case into a pool of molten metal while he’s trying to listen to Metallica and at the same time blasting every renegade soldier F.E.A.R.™ has to offer. Simple eh? Making it happen may not be all that hard, but making it happen to the level of performance that completely satisfies the highly demanding computer enthusiast market, well that’s another story entirely.

Today the speculation, supposition, and banter about what might be headed our way will be dissolved. In its place, if all predictions hold true, will arise lust and desire for a well engineered, highly expected product that will rock the entire graphics universe. There is of course the alternative scenario in which this product will be a total loser causing millions of loyal, unwavering NVIDIA fans move to the “dark side” quicker than alcohol turns urine on a Friday night. Given NVIDIA’s stellar track record I would bet on the former scenario rather than the latter.

We invite you to join Scott and I as we explore in detail the inner workings of GeForce 7950 GX2. We consider ourselves extremely fortunate to have garnered XFX’s top of the line “XXX” version of this card which comes from the factory with an default core clock of 570 MHz, and a combined memory clock of 1550 MHz for today’s review. 

FEATURES & SPECIFICATIONS

Features

• Full Microsoft® DirectX® 9.0 Shader Model 3.0 Support
• Built for Microsoft® Windows Vista™
• NVIDIA® SLI™ Technology
• NVIDIA® CineFX™ 4.0 Engine
• Full-Speed 128-Bit Studio-Precision Computation
• Transparency Antialiasing
• NVIDIA® Intellisample™ 4.0 Technology
• True High Dynamic-Range (HDR) Rendering Support
• HDCP Capable
• 90nm Process Technology
• High-Speed 512-Bit wide GDDR3 Memory Interface
• NVIDIA® PureVideo™ Technology
• NVIDIA PureVideo Features:
  • Adaptable Programmable Video Processor
  • MPEG-2 Decode Acceleration
  • H.264 Decode Acceleration
  • WMV Decode Acceleration
  • Inverse Telecine (3:2 & 2:2 Pulldown Correction)
  • Bad Edit Correction
  • Spatial-Temporal De-Interlacing
  • High-Quality Scaling
  • Video Color Correction
  • Integrated SD and HD TV Output
• UltraShadow II Technology
• Full-Speed 32-bit Color Precision
• Normal Map Compression
• NVIDIA ForceWare® Unified Driver Architecture (UDA)
• OpenGL® 2.0 Optimizations and Support
• Dual Dual-link DVI Support
• Dual 400MHz RAMDACs

GeForce 7950 GX2 vs 7900 GTX/GT Specs

The chart below is a comparison of the reference specifications from the GeForce 7950 GX2, the 7900GTX, and the 7900GT. The XFX “XXX” model of the 7950 GX2 that we reviewing today comes with a core clock of 570 MHz and a memory clock of 775 MHz for a combined memory clock of 1550 MHz. Other than the core clock and memory clock differences the XFX card appears to follow the balance of the NVIDIA reference specifications.

FEATURES & SPECIFICATIONS cont.

The following diagram shows how the GPUs on a single GeForce 7950 GX2 are interconnected via the custom PCI Express switch, and how the board interfaces to a system.

Some Newer Features

Multi-GPU and Multi-Monitor Modes:  The GeForce 7950 GX2 permits either multi-GPU or multi-monitor configurations. In multi-GPU mode both GPUs combine their rendering power to drive a single monitor. With multi-monitor mode, a single GPU drives both monitors, and all of the standard NVIDIA nView multi display modes are supported, along with Windows XP DualView modes. A control panel option exists to switch between multi-GPU and multi-monitor modes.

Extreme High Definition (XHD) Gaming:   The GeForce 7950 GX2 is designed for Extreme High Definition gaming (XHD), where games can be played at high widescreen resolutions up to 2560×1600. In fact, XHD has over seven times the picture clarity of native 1080i HD televisions and double the picture clarity of 1080p HD televisions. The widescreen format of XHD allows users to see more of their PC games, enhance their video editing, and even add useful extra screen real estate to Google Earth imagery.

PureVideo Technology with H.264 Hardware Decode:  NVIDIA’s PureVideo technology is the combination of a dedicated video processing core and software that accelerates and enhances high-definition video in H.264, VC-1 (coming soon), WMV/WMV-HD, and MPEG-2 HD and SD formats. PureVideo provides superb picture clarity, ultra-smooth video playback, minimal CPU utilization, and low power consumption. High-precision subpixel processing enables videos to be scaled to any size, so that even small videos look like they were recorded in high-resolution.

GeForce 7950 GX2 graphics cards are HDCP-capable (assuming you have an HDCP capable display and media player) and support the HDCP protocol. Each 7950 GX2 board includes a crypto-ROM chip that stores a key used for HDCP encoding of protected digital video content. The protected content must be HDCP-encoded by the GPU board prior to sending to an HDCP-capable digital display.

A CLOSER LOOK

When we unpacked the XFX® GeForce™ 7950 GX2 XXX from its shipping container we both noticed aesthetically pleasing the design and its associated color scheme were. I equated it to a thoroughbred grazing in a lush pasture of green with a sleek elegance emanating a personification of immense speed coupled with indignant pride. Scott’s guote was somewhat more poignant and to the point, something to the effect of “sure looks like a kick-ass card”. Oh well I think you get our point!

Did we mention that the XFX GeFORCE 7950 XXX is only 9 inches in length. Yep those days of trying squeeze your hard drives in and still be able to connect their SATA/PATA cables without sacrificing a bay or two should be over.

You will notice only one bridge connector in the above picture compared to two bridge connectors (one on each PCB) on a GeForce 7900 GX2 board. NVIDIA was able to remove one of the connectors to help reduce board space and installation complexity, while maintaining the same performance as the two-connector approach used in GeForce 7900 GX2-based Quad SLI.

Note that the 7950 GX2 is a dual-PCB design which occupies two PCI Express slot volume, and includes two dual-link DVI connectors. Also see the 7-pin HDTV-out mini-din connector. With the 7-pin HDTV-out mini-din, a user can plug an S-video cable directly into the connector, or use a dongle for YPrPb (component) or composite outputs. Our prior 9-pin HDTV-out mini-din connector required a dongle to use S-video, YPrPb, and composite outputs.

A CLOSER LOOK cont.

The images above show how much less crowded your system case will be using the XFX 7950 GX2 as opposed to using two separate SLI cards. The top picture shows the our test system with two 7800 GTX 512 Mb cards installed in SLI configuration. The bottom image reflects the same test system with the XFX 7950 GX2 XXX installed. Much less space with better performance and easier to cool…hmmmm!

The Card & Bundle

As we stated earlier the XFX “XXX” model of the 7950 GX2 comes with a core clock of 570 MHz and a memory clock of 775 MHz for a combined memory clock of 1550 MHz. Other than the core clock and memory clock differences the XFX card appears to follow the balance of the NVIDIA reference specifications.

Here’s a list of the package contents:

• XFX 7950 GX2 XXX Edition
• User’s Manual
• Quick Installation Guide
• Driver CD
• Molex-to-PCI Express Power Cable
• 2 x VGA/DVI Adapter
• S-Video Cable
• Component Video Out Cable
• Tomb Raider – Legend

New Control Panel

ForceWare Release 90 drivers introduce major usability changes to the control panel while delivering improved 3D gaming performance, better PureVideo quality, more SLI certified applications (over 240), and various bug fixes. Facilitating ease of use for both new and experienced users, the new control panel is “Vista-inspired” with simple navigation and clear, concise wording. For users who prefer to use the old style controls, they can still switch to “classic” mode. Similarly, OEMs can pick which control panel interface to use as the default in their drivers.

New video algorithms permit higher scores in benchmarks such as the HQV Benchmark, by now including noise reduction and image sharpening algorithms, and improved inverse telecine and deinterlacing algorithms. You should be able to attain a score over 110 in HQV. Here are a few screenshots of the look/feel/function of the new Release 90 drivers:

A CLOSER LOOK cont.

New Control Panel cont.

Motherboard Compatibility

The image below is an inclusive list of all the motherboards tested compatible and the respective BIOSes necessary to assure compatibility with the XFX 7950 GX2 XXX. This list was current as of May 31, 2006.

TESTING

Test System

• AMD X2 5000 running at overclocked to 2951MHz
• Foxconn CS1XEM2AA nForce 590
• 2GB of Corsair XMS2 8500
• XFX 7950 GX2 XXX Core Clock Default 570MHz, Memory Clock 1550MHz, running ForceWare 91.29 drivers
• 2 x NVIDIA 7800GTX 512MB in SLI default clock speed, running ForceWare 91.27 drivers
• 2 Seagate Barracuda 7200.10 750GB drives in RAID 1
• PC Power and Cooling 1KWatt SLI Power Supply
• Lian-Li V1200 Case
• Windows XP Pro SP2
• Dell 20″ LCD

Benchmarks

• 3DMark06
• Counter-Strike: Source, Video Stress Test
• Quake 4 v1.1
• F.E.A.R. v1.03
• Doom 3
• Far Cry

Testing Methodology

We will be testing the XFX 7950 GX2 XXX card in dual CPU mode compared to the dual 7800GTX 512MB cards in SLI mode. We will run the above captioned benchmarks on all both systems with the each GPU system at default speed with our socket AM2 5000+ processor overclocked to 2951 MHz. 3DMark06 will be run in default mode while all other tests will be run at the standard 1600 x 1200 resolution with Anti-Aliasing set to 4x and Anisotropic Filtering set to 8x.

The benchmarking tests will also be run on what we refer to as a “real world system” meaning we’ll run all the background applications that we run in every day life and not sequester them as are done by some reviewers to enhance benchmark results. Among the applications running in the background on our test system are:   Norton 2006 Internet Security (a real resource hog), Trillian, InCD, Steam and some other system applications that are too numerous to mention. Our hope in using this approach are to give you as close to possible the results you’d achieve if you were running these benchmarks on a similar system in your home. No other secondary enhancements to improve benchmark results will be run either.

TEST RESULTS

3DMark06

Counter-Strike: Source, Video Stress Test

F.E.A.R.

TEST RESULTS cont.

Far Cry

Quake 4

Doom 3

Impression

And….the winner is the XFX 7950 GX2 XXX, although not the stunning, kick-ass, bury ’em in the dirt type of victory you might have hoped for; we, for many reasons, feel the victory is pretty decisive. First, we’re comparing apples to apples or more appropriately two systems that are as statistically close as humanly possible. Second, there are no tests where the 7950 GX2 is not the winner. Third, and probably the most important reason is utilization of system resources:

1. We know from NVIDIA’s reference tests that 7950 GX2 reference system utilizes around 143 watts of power at max load. Since our XFX 7950 GX2 XXX is overclocked by roughly 15% we’ll add that to the power consumption as we at present don’t have the resources to measure the video card’s power consumption directly. This brings our total to somewhere in the neighborhood of 165 watts at maximum load. The 7800 GTX 512 Mb factory over clocked system that we compared the 7950 GX2 to uses around 275 watts of power in SLI configuration. That’s better performance at over 100 watts of power savings, nuff said!

 

• The 7950 GX2 takes up considerably less system space both vertically and horizontally in your case, we approximate it at conservatively at 25%. It doesn’t take a rocket scientist to also figure that with over 100 watts less power consumption and a decrease of roughly 25% in surface area occupied that you going to have a considerably more efficient system that doesn’t require near the system resources to cool.

 

All these factors considered and some more that we’ll mention in our conclusion lead us to name the XFX GX2 XXX a decisive winner in our testing.

CONCLUSION

Scott and I are extremely psyched after completing the review and testing of the XFX 7950 GX2 XXX. We feel without a doubt that both NVIDIA and XFX have brought products to the table that will obviously be of great interest to our readers, the computer enthusiasts of the world. There is no doubt in our minds that this product is setting the stage for many new and even more exciting things (like quad SLI using only two 7950 GX2s) to come.

The XFX 7950 GX2 XXX will have a debut price in the $625.00 – $650.00 USD range. This would be deemed expensive by the average computer jockey, but not at all by the enthusiast that’s shelled out almost twice that amount for two 7900 GTX 512Mb cards to run in SLI configuration. While this card will probably not yet compete heads up with the 7900 GTX 512 Mb cards in SLI configuration, it’s not very far off the mark at all and the slight variances certainly don’t justify double the price and almost double the system resources. This among the reasons stated above in our “Impression” certainly make the XFX 7950 GX2 XXX a product that will soar to great heights once the supply meets the obvious demand.

Can we recommend this product to our readers? The answer is a resounding “Hell Yes”! We’d go so far as to say it will probably be a contender for product of the year, especially given the fact that it can run on many non SLI boards. Though the current number of compatible motherboards are somewhat smaller than we’d like to see for the general population, as you can see most of the enthusiast-level boards (both Intel and NVIDIA based) reside on that list. We’re pretty sure with time, new motherboard BIOS, and new drivers that list will only be expanded.

We would also like to express our sincerest appreciation to all the wonderful people at XFX that so honored us by providing this product for review.

 

Pros:

+  Excellent core clock speed
+  Excellent memory clock speed
+  Extremely fast and capable
+  Better memory bandwidth than all it’s competitors
+  Excellent utilization of system resources
+  New and enhanced control panel

 

Cons:

–  Cost may preclude some users from buying

Final Score: 9.5 out of 10, and and our highest award, the Golden Bear Award