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basement dwellers last week on PS4 BF4 version * bu bu bu 720p is acceptable,doesn't matter as long it hits the 60 fps,resolution is not important* basement dwellers now : *lol 720p,so last gen and unacceptable,teh underpowered* Dat flip flopping :cool: #STAYMAD.Tessellation
That was hermits.
[QUOTE="ronvalencia"][QUOTE="Sonysexual1"] Are you claiming the two ACE unit reduces 7970 to 1/4 of PS4 (8 ACEs)? My 7970 has more active CUs which inturn has higher TDP than PS4's GPU. The amount of ACE units doesn't change the wavefront processing capability. btk2k2It looks like he is claiming that the PS4 has more ACE units than the X1, which is a statement of fact. He did not make any other remarks regarding the ACE units. What it does mean though is that the PS4 has can support a larger queue for compute data. Here is what the ACE units do.
Meanwhile on the compute side, AMDs new Asynchronous Compute Engines serve as the command processors for compute operations on GCN. The principal purpose of ACEs will be to accept work and to dispatch it off to the CUs for processing. As GCN is designed to concurrently work on several tasks, there can be multiple ACEs on a GPU, with the ACEs deciding on resource allocation, context switching, and task priority. AMD has not established an immediate relationship between ACEs and the number of tasks that can be worked on concurrently, so were not sure whether theres a fixed 1:X relationship or whether its simply more efficient for the purposes of working on many tasks in parallel to have more ACEs. One effect of having the ACEs is that GCN has a limited ability to execute tasks out of order. As we mentioned previously GCN is an in-order architecture, and the instruction stream on a wavefront cannot be reodered. However the ACEs can prioritize and reprioritize tasks, allowing tasks to be completed in a different order than theyre received. This allows GCN to free up the resources those tasks were using as early as possible rather than having the task consuming resources for an extended period of time in a nearly-finished state. This is not significantly different from how modern in-order CPUs (Atom, ARM A8, etc) handle multi-tasking.AnandtechThe advantage of having more is that you can queue up more tasks which means higher overall utilisation of the CUs.
Not quite right. The ACE units designed for 7970 has a dispatch capability to support it's 32 CUs i.e. a 32 CU equiped GCN has greater in-flight wavefronts when compared to lesser GCNs with less CUs.
7970 GE has a TDP around 220 to 250 watts which indicates greater active CU count when compared to similar process tech 18 CU equiped GCN i.e. PS4's GCN is estimated to be around 100-to-120 watts.
7970 GE's 250 watts @ 32 CUs / 2 = 125 watts @ 16 CUs which roughly equals to 7850's 130 watts @ 16 CUs.
http://www.tomshardware.com/reviews/radeon-hd-7970-benchmark-tahiti-gcn,3104-2.html
Note that each CU has it's own hardware scheduler and it has out-of-order dispatch on non-depandent wavefronts. 7970 has 32 hardware schedulers for 32 CUs.
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