Originally Posted by Ragnarok
All I can think of is they must be using tiling because the 360 doesn't have a larger enough frame buffer for two 108o frames. Therefore, it can't be full frame 1080p.
Why does it need two frames in the buffer at once? The Xbox 360 has 10 MB of ultrafast 256 GB/S embedded eDRAM it uses as its frame buffer. A single 32bit 1080p frame (by my calculations) takes 7.91MBs.
1080p Frame size = 32 bits * (1080 * 1920) / 8 (bits to bytes) / 1024 (bytes to KB) / 1024 (KB to MB) = 7.91 MBsReference to quote belowhttp://www.extremetech.com/article2/...1818127,00.asp
Note this post claims of course that "the full 10MB gets pretty much filled up with 1280x720 HD resolution, including Z, stencil, and anti-aliasing sub-pixel samples." This implies to me the Microsoft's rendering only processes one frame in the frame buffer at once. If Microsoft dropped the sub pixel anti-aliasing for example, they would likely have more than enough room for a 1080p frame. However, I'm not even sure that they would need to do that.
Remember that the 360 can do 4X 720p anti-aliasing in this 10 MB buffer (how it achieves this is technically more than my understanding). ATI designed the 10MB 256 GB/S buffer to work with a propriteraty anti aliasing algoritm. The numbers don't add up because they utilize the huge bandwidth to do things in a different way.
"ATI did clarify that although Microsoft isn't targeting 1080p (1920 x 1080) as a resolution for games, their GPU would be able to handle the resolution with 4X AA enabled at no performance penalty."ATI 1080p referencehttp://www.anandtech.com/tradeshows/...spx?i=2423&p=2
Originally Posted by Ragnarok
This has been debunked due to the fact that DVD drives are variable speed and operate far from their theoretical peak, while BD drives are constant speed and have a higher average transfer speed.
Not true. The PS3 2X Blu Ray drive reads at a constant 72mb/s. The Xbox 360's minimum read speed is about 66 mb/s for the innermost loop of the disc, and 132 mb/s for the outermost. If we assume a full disc, the Xbox 360's average transfer rate would be greater than 99 mb/s (99 is the average of the extremes, but there is more data area on the outer fast section of the disc than there is on the inner slow section of the disc). In actual practice, the average transfer rate can be even faster when developers master the discs with large streaming assets on the slow parts of the disc (such as video) and other time-sensitive assets on the faster parts of the disc (such as level load assets). In practicality, this would raise the 360's average transfer rate to a notable step above 99 mb/s for game assets that need the speed. The PS3 reads the entire face of the disc at a constant 72 mb/s. I would conservatively estimate that the Xbox 360's disc transfer speed is roughly 1.5 times that of the PS3's in practical situations (implying an average transfer rate for speed sensitive assets of 108 mb/s for the 360). Only in the most extreme circumstance (i.e. an extremely small image size for a 360 game) would the average transfer rate for the 360's DVD drive fall below the PS3's Blu-Ray drive. In games that small, transfer rate isn't likely a noticeable issue anyway.
To see this graphically, look at the second line graph (Blu-ray vs 12X DVD read speed) on this page:http://www.gamespot.com/pages/profil...9&user=skektek
Note that the PS3's Blu-Ray drive in the blue dot above 2X. The slowest the Xbox 360's drive reads is the red line (which is only slightly under the PS3's blue dot), and the fastest it reads is the green line (closer to the Blu-Ray 4X dot). A 3X Blu-Ray drive would be similar in transfer to the Xbox 360's 12X DVD drive.
However, it is not all about transfer speed though. I wouldn't personally think that this puts a nail in the PS3's coffin. The PS3 will be great in its own right. It's storage size will be a benefit for future games. The HDMI 1.3 solution is a awesome. I'm bullish about all the consoles. However, there is not one console this generation that wins in all categories.
Ragnarok, I enjoy talking to you, but might I respectfully request that if you try to correct me you site reputable sources rather than just making claims? When I correct you I'm trying to support my claims as much as possible. I'm sure there is much we can learn from one another. I look forward to your future posts.