NVIDIA RIVA TNT2 - What can TNT2 do for ya?

On a first look you can say that the NVIDIA TNT2 is only a higher clocked TNT chip. But there are some differences. The first is that TNT2 is manufactured in 0.25 micron. The TNT was made in 0.35 micron. This results in a lower voltage power and less heat production. The result is that you can use higher clock rates.
Other internal changes in TNT2 are the support of up to 32MB SDRAM or SGRAM. You can use this amount of RAM for higher game- and desktop resolutions and for more high detail textures in games. The max resolution you can use is 2048x1536. This is made possible by an 300MHz RAMDAC. The TNT2 cards Iīve tested also do have a better image quality. The desktop is sharper than on TNT cards that come with a 250MHz RAMDAC. In the following a comparsion between TNT and TNT2:

NVIDIA states that they did other additional changes in the chip design but they donīt talk about details here.

TNT2 and TNT2 ULTRA

You can get two different TNT2 versions: TNT2 and TNT2 ULTRA. The only difference between these two versions are the clockspeeds the cards are running at. The TNT2 is specified for 125MHz chipclock and 150MHz Memoryclock. The ULTRA does 150MHz chip and 183MHz memclock. NVIDIA screens the chips after they are manufactured and tests them for speed. The chips that can run faster are arranged as TNT2 ULTRA. The real difference between normal and ULTRA cards are the memory chips used on the cards. ULTRA cards should have memory with a access time of 5 to 5,5ns to run fast at high clockspeeds like 183MHz or above. The important point here are the refresh-times (waitstates). The memory chips need some rest after access until you can access them again. And this rest is shorter with faster memory chips. The TNT2 ULTRA reference card I got runs with 8ns SDRAM at 183MHz. The chips are stressed a lot at this clockspeed. Overclocking them to 190Mhz results in system crashes. I got an ASUS V3800 Deluxe with TNT2 ULTRA (150/183) that uses 5,5ns SGRAM. You get higher results with this card because of its faster memory. Another point is that you can overclock faster RAM to higher values again. Hercules for example anounced a TNT2 card with a clockspeed of 175/210 MHz and also give you an overclocking utility.

The clockspeeds of 125/150 and 150/183 are not fixed. Every manufacturer can use values he wants. There are Diamond, Guillemot and Hercules who announced TNT2 ULTRA cards with higher clockspeeds than 150/183.

RIVA Station 1999 - Lars Weinand