Canopus SPECTRA 2500 Riva TNT

Unfortunately there is only so much thousands of well written lines of code can do, limitations are placed on the software end of things therefore requiring hardware support to bridge the gap and fill the void produced where software capabilities ends and the hardware picks up the rest.  Who has decided to step forward and present us with their interpretation of the visible light we deserve?  None other than Canopus Corp. with their rightfully titled, SPECTRA 2500 2D/3D graphics accelerator based on the nVidia Riva TNT Chipset.Usually late to the game, as far as releasing products based on new chipsets is concerned, Canopus jumped the gun this time with the release of their first product based on the nVidia Riva TNT chipset, the SPECTRA 2500.

Starting from the ground up, nVidia, like any well rounded manufacturer would, decided to concentrate on the weaknesses of their previous product, the Riva 128/ZX, and improve on it to a point of near perfection.   In order to understand what the Riva TNT is all about you must first understand what inspired the creation of the chipset, in essence, what the Riva 128 lacked.

128 Reasons not to buy nVidia

After the initial release of the Riva 128 chipset it seemed as if the chipset itself was reason enough to leave nVidia out of the competition when it came to overall quality.  Suffering from poor image quality, poor implementation of the AGP specification, an annoying 800 x 600 Z-Buffered resolution limitation, not to mention poor performance on slower systems.  In a cheap attempt to correct some of those problems nVidia went ahead with the release of an intermediate chipset, the Riva 128ZX, which boasted an AGP 2X compliant interface as well as support for up to 8MB of on-board RAM.  However the improvements weren't enough to justify ditching your Voodoo or Riva 128 for a card based on a chipset that sounds like it was a discontinued Camaro.  Luckily nVidia realized that the market needed much more than a Riva 128 with a new name, so it was back to the drawing boards for the nVidia engineers and back to the hyping spree for the Public Relations directors as nVidia gave the world of 2D/3D combo chipsets another try...the result?  The nVidia Riva TNT, a chipset whose description on paper could have been the best graphics accelerator of 1998.

What you see isn't always what you get

According to the first press releases directly from nVidia, the Riva TNT chipset was supposed to be manufactured using a 0.25 micron process, clocked at 125MHz, and was supposed to be powerful enough to be a Voodoo2-killer because of its 250 Million Pixels per Second fill rate.  According to the Canopus Spectra 2500 sitting on the test bench AnandTech reviewed, the Riva TNT chipset was manufactured using a 0.35 micron process, is clocked at 90MHz (although there is a chance of Canopus shipping their boards at 100MHz), and has a fill rate in the range of 190MP/s.   Two statements that are almost as different as night and day, and two statements which will end up ruining nVidia's credibility in the future.

Directly from the source, nVidia claims to have a 0.25 micron shrink in the works for the TNT, however that conversion won't take place until sometime in 1999, meaning that the TNT will stay clocked at the 90 - 100MHz range for at least a few more months, when it will most likely switch off to the 125MHz clock setting it was supposed to be shipped at after receiving its 0.25 micron core.   In spite of the fact that the public was blatantly lied to by nVidia about the potential of the TNT, technically nVidia never said when their TNT would be a Voodoo2-killer, so we can't really blame them now can we?  You better believe we can.

Cramming a total of 7million transistors into the 0.35 micron package of the Riva TNT, nVidia managed to create an extremely hot chip that would require significant amounts of cooling to get it to operate at the original 125MHz setting nVidia was claiming.  While a TNT chip manufactured using a 0.25 micron process could easily be clocked at 125MHz without too much added cooling necessary (a heatsink would most likely do just fine), a 0.35 micron TNT is another question, which is why nVidia reduced the recommended clock speed to 90MHz.  As you can tell, this definitely decreases the performance of the TNT, but we'll talk about performance figures a little later. 

If you're looking for a $200 card that can beat a Dual Voodoo2 SLI setup then you are better off dreaming for a little while longer, as the TNT isn't the chipset that will do that.  While it may provide as a decent Voodoo2 alternative, it is definitely not something you'll want to consider a Voodoo2-killer, simply because of its current price/performance level. 

What do you get with the Riva TNT?

What the TNT does bring to the table is fairly impressive considering that in relative comparison, their last 2D/3D chipset was a total bomb in terms of overall quality.  The TNT chipset supports 3D, Z-Buffered, resolutions of up to 1600 x 1200 and, like the Matrox G200, does support 32-bit rendering giving it a slight visual advantage over 3Dfx's Voodoo2 chipset.  The image quality on the TNT is vastly superior to that of the original Riva 128, but better yet, it is virtually on par with that of the Matrox G200.  Telling a G200 screen shot from a TNT would require a considerable amount of thought and such a comparison would definitely be reserved for those with an eye for the smallest differences among images, for the rest of us, the TNT's image quality can be considered to be virtually on-par with that of the G200.  So is the TNT a G200?  Absolutely not, the similarities between the two chipsets ends here as the TNT shifts into high gear leaving Matrox's precious 2D/3D wonder in a cloud of dust.

The 128-bit graphics engine of the Riva TNT chipset is intended to be a direct competitor to the best of the best when it comes to 3D accelerators, bringing a 250MHz RAMDAC for crisp 2D output keeps the TNT on top of 3Dfx's Voodoo2 making the chipset a true high-end 2D/3D combination solution.  Featuring dual internal texture pipelines, the TNT has been claimed to be able to process multi-textured objects in a single pass, picking up where 3Dfx left off, nVidia managed to accomplish this using a single chip instead of using the two separate texelfx processors the Voodoo2 uses.  The effectiveness of this approach is another question, however all numbers aside, on paper, the TNT took its time shaping itself to be a true winner.

All of this power is harnessed on a short reference board designed to fit into an AGP slot in order to take full advantage of the AGP 2X specification, transferring data on the sidebands of the AGP signal as well as during the peaks.

So what has Canopus managed to do with nVidia's over-hyped TNT chipset?  Let's take a look and find out...