AMD’s RV770 has 40 texture memory units?
After that FXvideocards posted the texture fillrate of Radeon HD 4850 we can calculate that the RV770 probably has 40 texture memory units, rather than 32. From an architectural point of view that does makes a bit more sense.
The texture fillrate is said to be 24.0GT/s and since we know that the core clock is 625MHz we can calculate the amount of TMUs by dividing the fillrate with the core clock and then we get ~38, rounded up to 40. Not proof, but certainly a possibility. There have been talks about a separate domain clock, and 32TMUs clocked at 750MHz does result in 24GT/s, but separate domain clocks hasn’t been proved and we consider this nothing but speculation.