| DonFerrari said: Also the other aspect that needs more detail on the architeture is how much the extra frequency will help PS5 against the choice for less CUs. |
First and most important, the 2.23 vs 1.825 GHz difference is valid for everything in the gpu, not just the cus. This includes command processor, raster operations, geometry engines, all the cache and register memory, hardware companders, whatever else is implemented into the gpu (like the Tempest stuff which makes the PS5 the clear winner in the VR department right out of the gate). So if your entire life circled around vector processing, you'd be comfortably ahead with the XSX's cu advantage. That includes Ray tracing, the XSX can roughly calculate 380billion vs PS5's 320billion intersections/s (the PS5 might gain some ground thanks to the faster caches, and boy does rt depend on caches!). This winning scenario assumes that the XSX has the capability to keep all the 52cus busy at all times, whereas the PS5 only has to keep 36cus busy all the time. Now if we look at the history of AMD keeping all its cus busy all the time, that track record is somewhat checkered, to put it mildly. You might remember all the talk about AMD not being able to have more than 64 cus in its cards. Of course there never was a hardware limit (except space constraints, obviously), but the fact that more than 64 cus would simply show such a lousy increase in performance that it basically was money thrown down the gutter. If we assume (big IF) that this has changed with rdna2, then more cus is better, obviously. Keep in mind that keeping more cus busy means more threads which means more command processor activity which means more cache activity (at a lower speed in the XSX compared to PS5). If not, then less cus is better. I hope you are beginning to see that merely shouting "12.1TF vs 10.3TF" sounds very good to the gamerzzz and pr crowd, shouting it to the developers who actually have to use the gpus would make you look a little foolish.
Games will eventually tell who is right. Probably there won't be a right or wrong at all. There's always a solution to hide a 10% deficit in a particular area. One drawback of faster clocks should be mentioned, too. If you have to go to main memory, you lose a little more time on fast clocks than on slower clocks. But if you have to go that road, you've lost anyways. As for the rt advantage, nobody knows yet if simply using a few less rays on the PS5 will nullify the XSX's advantage.
In the end, the games will show who is "right" (and there really isn't a clear right or wrong to start with). Sony with its first party galore still has a clear advantage in the race, if they can show it soon after/with the launch.
Last edited by drkohler - on 21 March 2020
