[H]ard|OCP

Navigation

• [H] Forums
• Archives
• Search
• [H] Folding

BFGTech GeForce 9800 GTX

NVIDIA is launching the successor to the GeForce 8800 GTX! Will the new GeForce 9800 GTX live up to the impressive legacy of the 8800 GTX? Is the 9800 GTX an upgrade? Or is it a step backwards? We evaluate the new card from BFGTech.

Introduction

Today marks the release of NVIDIA's replacement to the longstanding king of discrete desktop graphics performance. The G80 based GeForce 8800 GTX has had an unusually long time in the limelight. Its performance crown has been virtually unchallenged since its debut on November 8, 2006, almost a year and a half ago. Today, however, the slot occupied by the venerable GeForce 8800 GTX is being refit for the new breed: The predictably named “GeForce 9800 GTX.”

NVIDIA GeForce 9800 GTX

Built on a 65nm manufacturing process and encompassing a whopping 754 million transistors, the GeForce 9800 GTX GPU resembles the G80 in a few ways, but also packs some surprising changes. It has 128 streaming processors, though NVIDIA now refers to them as "processor cores," and 16 ROPs, which NVIDIA now refers to as "render back-end units." The clock rate of the streaming processors on the GeForce 9800 GTX is set, by default, at 1688MHz. The GPU core run at 675MHz, and the 512 MB of GDDR3 memory runs at 2.2GHz on its 256-bit wide bus.

9800 GTX Changes

The most interesting changes here are the memory capacity and the memory bus. Almost 18 months ago, the GeForce 8800 GTX came out with a staggering 768 MB of memory on a very wide 384-bit bus. But now, the GPU that comes to replace it comes to the party with 1/3 less memory and narrower data bus. It could be argued that a 768MB framebuffer and a 384-bit memory bus were overkill when the GeForce 8800 GTX was released. Most games at that time barely exceeded the 512 MB framebuffer. But that was before Crysis. When Crysis hit, the GeForce 8800 GTX suddenly seemed insufficient. Now, NVIDIA introduces a video card with a smaller framebuffer and a narrower data bus than the product it intends to replace. It is not hard to argue that these changes are bad for the high-end enthusiast user that this product targets, so some of this has left us wondering about NVIDIA’s decisions.

But aside from the narrowing of the bus and the shrinking of the framebuffer, there are other changes too, and for the better. The GPU core on the GeForce 9800 GTX is 100MHz faster than the G80, and the streaming processors are 338MHz faster. The memory too has been accelerated, up by 400MHz from the GeForce 8800 GTX's deceptively pokey 1.8 GHz DDR clock rate. At that clock speed, the memory has a maximum theoretical throughput of 70.4GB per second, which is down by 16GB per second from the capabilities of the GeForce 8800 GTX.

The GeForce 9800 GTX GPU itself is manufactured on a 65nm process and contains 754 million transistors, making it actually more complex than the G80. The video card as a whole is also rated at 156 watts TDP, which is 29 watts less than the GeForce 8800 GTX video card which weighs in at 185 watts.

New Technology Features

The GeForce 9800 GTX supports 3-way SLI. Enthusiasts are quite familiar with SLI, of course, but 3-way SLI is a relatively new thing. Prior to the introduction of 3-way SLI, NVIDIA offered only single-card solutions and 2-way SLI solutions. For those who may be unaware, SLI offers a way of increasing gaming performance by adding a second identical video card to the system. The video cards are connected by a small SLI bridge plugged into a small card edge connector on the video cards. Both video cards framebuffers must contain the same data, and you cannot use multiple displays when SLI is active. Essentially, that means that two video cards with 768 MB of memory combine to make one more powerful video card with 768 MB of memory, driving only a single monitor. Three-way SLI allows the gamer to add yet another identical video card to the mix, but does not alleviate the single monitor restriction, and it still requires the video memory on each video card to have the same contents. Please note that 3-way SLI is not exclusive to the GeForce 9800 GTX. Both the GeForce 8800 GTX and the GeForce 8800 Ultra also support this feature.

The GeForce 9800 GTX also supports a new feature called HybridPower. HybridPower can only be used with supported motherboards. Those motherboards have to have an NVIDIA chipset and an on-board graphics solution. In the simplest possible terms, HybridPower allows the GeForce 9800 GTX to be powered off entirely when not rendering 3D images, allowing the on-board graphics adaptor to handle lightweight tasks such as rendering Windows, including Aero in Windows Vista. This does not require the user to unplug his or her monitor from the video card and plug it into the motherboard's port. When enabled, HybridPower "redirects" the output of the GeForce 9800 GTX to the integrated adaptor's port. Logically, this would not work for multimonitor solutions, unless NVIDIA plans to make some nForce motherboards with integrated graphics sporting more than one DVI connector. And in any case, HybridPower is a subset of the larger Hybrid SLI technology, so multiple displays may not work with it anyway. We have yet to test this feature as we have not had motherboards rolled out to us that support the feature as well. Simply, the needed hardware is not available yet and we are unsure when it will be.

On top of all of that, the GeForce 9800 GTX also supports NVIDIA's PureVideo HD, a hardware-based acceleration technology for decoding High Definition Video, such as Blu-ray and the now-fading HD-DVD. Previously, only NVIDIA's lower-spec GeForce 8600 and 8500 series supported PureVideo HD. The much more powerful and much more expensive GeForce 8800 GTX and GeForce 8800 GTS did not support this feature. Essentially, PureVideo HD offers 2 things: performance enhancement and image quality enhancement of HD video sources. By performance enhancement, what we mean is that the driver offloads the HD video decoding process from the CPU to the GPU, which is much more ideally equipped to handle such calculations. By way of image-quality enhancement, NVIDIA offers Dynamic Contrast Enhancement and Dynamic Blue, Green, and Skintone Enhancement. Dynamic enhancement means that the contrast and color optimization curve is based on a histogram calculated per frame, rather than a pre-selected static optimization curve. Dynamic optimization allows for contrast and color enhancement without overexposing highlights or destroying shadows.

Pricing

NVIDIA tells us that GeForce 9800 GTX video cards should be coming to market between $299 and $349 USD. That makes these video cards quite a bit cheaper than the GeForce 8800 GTX was when it was released. Today, it means that the GeForce 9800 GTX is coming in just below the current average cost of a GeForce 8800 GTX. Obviously, we will know more about this as the day progresses and we will be updating our conclusion page to reflect retail selling prices as we see the 9800 GTX cards go up for sale.