In what major ways is the NV2A different than the geforce 4?

[Luminescent]

In what major ways is the NV2A different than the geforce 4? Clock for clock is it more efficient? I remember reading 116 million vertices per second on the NV2A(233MHz), while the NV25 (250MHz) outputs 113 million ? I have also read it houses a similar cache architecture, can execute similar anti-alaising methods, anything else (?).

 

[Luminescent]

Anyone?

 

[ERP]

Well obviously NV2A contains a Northbridge and NV25 doesn't.

From a feature standpoint they are extremely similar, NV2A lacks the ability to downsample in the DAC. And there are probably minor differences in things like triangle setup rate etc. But I don't have access to any detailed NV25 documents to be able to comment on this.

 

[megadrive0088]

Here are some of the differences that I can recall offhand:
NV25 contains a new anti-aliasing unit, AccuView (TM), that NV2A does not have. Nv25 has Lightspeed Memory Architechure 2, while NV2A has either LMA ver 1 or an updated version of LMA ver 1 from GeForce3. The vertex and pixel shaders in NV25 are more refined (tweaked) than NV2As. NV25 also has alot more raw memory bandwidth (10.4GB/sec) than NV2A (6.4GB/sec) and NV25's b/w is not UMA.

When XBox was officially annouced by MS, they (MS and Nv) said that it would use NV25. then they said it was something between NV25 and NV30 (a MS rep said NV27.5) but in reality, the NV2A is inbetween NV20/GF3 and NV25/GF4ti - I'd call it NV23. It was also reduced in performance conciderably from 300Mhz to 233Mhz, thus cutting down its pixel/texel fillrate and vertex rate.

I'm still waiting to see realtime graphics on XBox that are as good as that awesome mech demo MS used in March 2000 to show off their Xbox concept.

 

[megadrive0088]

I wish XBox specs were more like:

NV25/GF4ti @ 300 Mhz
P4 1.5 GHz or at least P3 1Ghz
128 MB DDR main + audio memory
128 MB DDR graphics memory on seperate bus

12.8 GB/sec bandwidth for graphics
3.2 GB/sec bandwidth for CPU+Audio
audio as it is.

and lasts until 2006 when an NV55-based XB2 comes out

 

[Glonk]

Wasn't the 300GHz figure for when they said they were using a Gigapixel chip? Then it went to 250 for Nvidia, then 233 before launch. IIRC, that is.

 

[mech]

Nope. 300Mhz NV2A and a 600Mhz P3.

 

[Tagrineth]

Nope. 300Mhz NV2A and a 600Mhz P3.

Hah! Just like Nintendo they boosted the CPU and lowered the vid chip for release

 

[-tkf-]

I'm still waiting to see realtime graphics on XBox that are as good as that awesome mech demo MS used in March 2000 to show off their Xbox concept.

That was a prerendered 3D MAX Video, hell the studio that made the video even used it for PR on their website

 

[Laa-Yosh]

I'm still waiting to see realtime graphics on XBox that are as good as that awesome mech demo MS used in March 2000 to show off their Xbox concept.

That was a prerendered 3D MAX Video, hell the studio that made the video even used it for PR on their website

However, I'm quite sure that something pretty similar could be created in real-time using the Halo2 or Doom3 engine on the Xbox. 2003 Q3-Q4 should bring that quality to at least some of the Xbox games, so you might only have to wait another year...