this might be interesting to benchmark! id love to test a 4870 vs a 5870 with half its blocks disabled to see how big of a diference this makes!

The computing cores can communicate on both local and global levels. ATI claims a considerable increase in cache bandwidth. Particularly, the speed of fetching data from the L1 cache is now as high as 1 terabyte per second while the bandwidth of the link between the L1 and L2 caches is increased to 435GBps. The L2 caches have become larger from 64 to 128KB.
xbitlabs keeps mentioning the reduced bandwidth "probably" causing some impacts at high resolutions compared to the 4870x2... they claim to have written this passage of the article before doing any tests, but i dont buy it
im pretty sure they KNEW what perf was like when they wrote this part...

anyways, if bandwidth is really the limiting factor, then why doesnt the 5870 drop behind the 4870x2 notably at high resolutions and with high anti aliasing modes, and why doesnt the 5870 perform notably better at low resolutions where the memory bandwidth doesnt matter?

yes, you CAN see this trend, its definately there, but its veeery subtle... we are talking about a few percent points here, nothing mayor you would expect from the 5870 having more than 30% less bandwidth than a 4870x2...

i think i found something...
rv870 is a REALLY massive chip with a huge load of raw processing power... keeping all those sps busy is not easy... and i think thats whats holding the 5870 back...



thread limit was only increased from 768 to 1024...
could this explain the limitation? 768 to 1024 is only a 30% boost... and a 5870 is roughly 40% faster than a 4890...