XBox2 specs (including graphics part) on Xbit

[Joe DeFuria]

OK, so I'm having trouble deciphering the read/write peak bandwidth between the GPU and edram.

Z/Stencil value is 32 bpp, correct?

1) 1024 bits/clock when writing reading only z/stencil to EDram
2) 768 bits/clock when writing color+z/stencil to EDRam

3) 512 bits/clock when reading color only from EDRam
4) 512 bis/clock when reading z/stencil only from EDRam

Correct...or am I just clueless?

 

[McDusty]

hmm, it mentions a hard disk.

Internal or external i wonder

 

[Joe DeFuria]

Um, you were on a roll untill here. Hopefully, note I said hopefully, the console vendors will make it adventageous to move beyond the DTV resolutions of 480i or 480p. There has been talk of 720p and 1080p, take that as you will.

Still 1080p is still quite a bit less than 1600x1200p. Though honestly, I'm thinking more along the lines of 720p and 1080i support...as 1080p just isn't common enough to demand support for it, AFAIK.

In the end, I see pixel shading ops per clock as much more important than raw fill-rate for TV based consoles....whereas in the PC space there's still a bit more need to jack up raw fill rates.

 

[plat]

Seems reasonable for a console...considering its 500 Mhz, and we're still talking TV resolutions...not 1600x1200 PC resolutions.

Um, you were on a roll untill here. Hopefully, note I said hopefully, the console vendors will make it adventageous to move beyond the DTV resolutions of 480i or 480p. There has been talk of 720p and 1080p, take that as you will.

i'd say its a givin, the current xbox supports 720p and 1080i.

 

[Joe DeFuria]

i'd say its a givin, the current xbox supports 720p and 1080i.

Yes, but games are not required to support those resolutions, because the power just isn't there.

It would not be surprising to me to see MS require devs to support for 720p and 1080i in this gen.

 

[Vince]

In the end, I see pixel shading ops per clock as much more important than raw fill-rate for TV based consoles....whereas in the PC space there's still a bit more need to jack up raw fill rates.

Ohh, definitly. I think the prominence of computational resources is a concept we can both agree to I just wanted to point out that TV resolutions is moving up as well - an acyclic happening for Consoles.

 

[Joe DeFuria]

Ohh, definitly. I think the prominence of computational resources is a concept we can both agree to I just wanted to point out that TV resolutions is moving up as well - an acyclic happening for Consoles.

Roger that.

 

[madshi]

Still 1080p is still quite a bit less than 1600x1200p.

1920*1080 = 2073600
1600*1200 = 1920000

 

[ninelven]

Still 1080p is still quite a bit less than 1600x1200p.

1080p (1920x1080) would be more demanding than 1600x1200; however, personal preference and application come into play when evaluating resolutions. The sad part is I am not aware of any TVs which even truly support 1080i yet.

 

[PiNkY]

Still 1080p is still quite a bit less than 1600x1200p.

1080p = 1920 * 1080 = 2073600 > 1920000 = 1600*1200

I don't think it'd be a wise move to require software developers to support the various hdtv resolutions. you'd have to compromise a lot on pixel shading if your game has to run with 30fps@1080p compared to just having it run at normal tv resolutions. Also i'd doubt that hdtv will even reach double digit market penetration by 2005-2006.

 

[KimB]

It seems to me that this graphic is a plan for the X-Box 2. It's what Microsoft wants. It's not necessarily based upon anything actually in development.

 

[Joe DeFuria]

Still 1080p is still quite a bit less than 1600x1200p.

1920*1080 = 2073600
1600*1200 = 1920000

My mistake...I was neglecting 16:9 aspect ratio.

 

[Joe DeFuria]

It seems to me that this graphic is a plan for the X-Box 2. It's what Microsoft wants. It's not necessarily based upon anything actually in development.

Well, if the plan is to productize it by even x-mas 2005....something better be in development.

 

[KimB]

It seems to me that this graphic is a plan for the X-Box 2. It's what Microsoft wants. It's not necessarily based upon anything actually in development.

Well, if the plan is to productize it by even x-mas 2005....something better be in development.

Right. I was trying to state that anything that is currently in development may well differ from that plan. As an example, depending upon engineering concerns, the eDRAM may be reduced or dropped altogether.

 

[DemoCoder]

It better support HDTV 720p and 1080i native. For a console to be launched in 2005 intended to last 5 years until 2010 and not be designed from the ground up to run HDTV resolutions at 60fps would be a real shame.

Anyone have any info on the PS3 GS for comparison? I have the impression that the broadband engine will own this CPU wise?

 

[Vince]

Right. I was trying to state that anything that is currently in development may well differ from that plan. As an example, depending upon engineering concerns, the eDRAM may be reduced or dropped altogether.

Right. And Joe's still right. The designs have basically been locked down and the specs have been in developers hands for several months now. Any change, especially one as large as dropping the eDRAM, would constitute a major failure. These things are pretty static, Sony has two years of R&D prior to today on MS and possibly a year after today on them - so there is alot of set-piece thinking when designing a console.

PS. Democoder, wrong thread, but I'd agree. The MPU's won't even be relative if it's compared with a BE-esque processor. Also, System and method for digital image selection and just skim over the BS posts the discussion. Perhaps just revive the thread if you want to discuss this.

 

[plat]

Still 1080p is still quite a bit less than 1600x1200p.

Also i'd doubt that hdtv will even reach double digit market penetration by 2005-2006.

true but you have to take into account the type of person who plays video games. i'm sure when you do that the ammount of hdtv to sdtv ratio goes way up.

 

[Natoma]

Even high end televisions today have a hard time displaying 1080p due to the hardware requirements. We won't see 1080p consoles until XB3/PS4/N6. I agree. 720p is quite reasonable and frankly expected, especially since 2006 is the date when Digital signals (not to be confused with HDTV) become the FCC broadcast standard, as well as the continually falling prices of home theater systems and big screen televisions.

 

[Megadrive1988]

DemoCoder:

It better support HDTV 720p and 1080i native. For a console to be launched in 2005 intended to last 5 years until 2010 and not be designed from the ground up to run HDTV resolutions at 60fps would be a real shame.

I agree wholeheartedly!

I'd expect all games to support 720p / 1080i and 480i / 480p

 

[DemoCoder]

Natoma, even 1080i still needs to be supported, and it still requires you to render a 1920x1080 framebuffer, you just downconvert it to 1920x540 to output a field.

With only 10mb of EDRAM, FSAA and HDTV resolutions are not supportable. 1280*720*8bpp*4xfsaa = 29mb (yes, compression can be used, but you cannot depend on a guaranteed compression ratio, you have to allocate a buffer the size of the worst case). If you use 64-bit FB for HDR, it's worse: 1280*720*12bpp*4x = 44mb. Of course, it's all even worse for 1080i.