Praised for its efficiency (performance per watt) and recommended by admin89 and other members of this forum, the Radeon HD7750 GDDR5 (@ 72GB/s) card should be a decent upgrade from those 'el cheapo' low-end cards (with GDDR3 @ 28 GB/s) with more than enough pixel throughput, memory bandwidth and shader processing power to run almost any title at 4xIR with VSync.
So after getting one of these cards for testing, the first thing I did was a quick Dolphin benchmark to compare the performance of the new card to an old, dirt cheap, HTPC grade card (the HD5570 GDDR3 @ 28 GB/s).
Both cards were tested on the same PC with the latest version of Dolphin (exact same settings) and the latest official drivers from AMD.
But here's the shocker: The performance results of the new card were surprisingly bad - the opposite of what's expected from a card with such specs.
How is it possible that a low-end HD5570 from two generations ago with fewer (and less powerful) processing cores, with only 1/3 of the memory bandwidth and 2.5x lower pixel fillrate runs circles around this new card when using the D3D11 renderer ?
The modern and much more powerful 7750 performs so bad (with the D3D11 renderer) that it's unable to render an undemanding scene like the DKCR 'Start Game' screen (the one with the stone ape statues) at 60fps (56fps) @ 1x IR (!) with VSync turned off.
Enabling Dolphin's frame limiter cripples the performance even more, while there's almost no effect on the old card.
Increasing the IR to 4x drops the framerate even further.
It was really shocking to see the 'crappy' old 5570 running this screen at a blazing fast 89 fps at 1xIR and still managing to pump out 65 fps at 4xIR.
There's no such problem with the D3D9 backend (or even the slow-ass OpenGL backend). You can crank up the IR to 4x and still get rock-solid 60fps with VSync + frame limiter enabled (the speed is back to normal: 89fps @ 1xIR).
But D3D11 should perform a whole lot better with these modern cards (significantly faster than D3D9), since they're designed / optimized for D3D11.
HD7750 should be able to handle 4xIR + VSync (D3D11) with ease.
Note: With the old, low-end 5570, D3D11 was performing noticeably faster.
Here are some other (even more shocking) benchmark results :
=====================================================
Dolphin D3D11 BENCH PART I - HD7750 vs. HD5570 (+ some HD6850 results)
=====================================================
MoM @ 4xIR (D3D11), save state of a more demanding (GPU-heavy) scene
-----------------------------------------------------------------------------
HD5570 GDDR3 = 52 fps (same as the HD6850)
HD7750 GDDR5 = 43 fps (!)
SMG1 Observatory @ 2xIR (D3D11):
----------------------------------------------
HD5570 GDDR3 = 47 fps (same as the HD6850)
HD7750 GDDR5 = 42 fps (!)
DKCR 'Start Game' Screen @ 4xIR (D3D11) + VSync:
-------------------------------------------------------------------
HD5570 GDDR3 = 60 fps (same as the HD6850) --> http://postimage.org/image/54iqnp4v5/full/
HD7750 GDDR5 = 41 fps (!), even at 1xIR --> http://postimage.org/image/ruhljxim9/full/
======================================================
DOLPHIN BENCH PART II - D3D9 vs. D3D11 performance on the new HD7750
======================================================
MKWii Menu (Single player) @ 4xIR - really demanding part, needs *a lot* of GPU 'juice'
----------------------------------------------------------------------------------------------------------------
D3D9 = 68 fps
D3D11 = 21 fps (!)
FZERO Machine Select Screen @ 4xIR
-----------------------------------------------
D3D9 = 31 fps
D3D11 = 6 fps (!)
SMS (with EFB to RAM) @ 4xIR
----------------------------------------
D3D9 = 31 fps
D3D11 = 17 fps
DKJB Banana Kingdom (end of level banana bunch) @ 4xIR
----------------------------------------------------------------------------
D3D9 = 71 fps (same as the HD6850)
D3D11 = 50 fps (HD6850 = 68 fps)
Is this an issue with all cards in the HD7000 series ?
Is there anyone with a HD7000 series card who could test and compare the difference in performance between the D3D9 and D3D11 backends ?
Emu: Dolphin GIT 3.0-631 (latest revision)
OS: Win7 SP1 x64
Latest GPU drivers: Catalyst 12.4 WHQL (8.96.1) and 12.5 beta (8.97)
So after getting one of these cards for testing, the first thing I did was a quick Dolphin benchmark to compare the performance of the new card to an old, dirt cheap, HTPC grade card (the HD5570 GDDR3 @ 28 GB/s).
Both cards were tested on the same PC with the latest version of Dolphin (exact same settings) and the latest official drivers from AMD.
But here's the shocker: The performance results of the new card were surprisingly bad - the opposite of what's expected from a card with such specs.
How is it possible that a low-end HD5570 from two generations ago with fewer (and less powerful) processing cores, with only 1/3 of the memory bandwidth and 2.5x lower pixel fillrate runs circles around this new card when using the D3D11 renderer ?
The modern and much more powerful 7750 performs so bad (with the D3D11 renderer) that it's unable to render an undemanding scene like the DKCR 'Start Game' screen (the one with the stone ape statues) at 60fps (56fps) @ 1x IR (!) with VSync turned off.
Enabling Dolphin's frame limiter cripples the performance even more, while there's almost no effect on the old card.
Increasing the IR to 4x drops the framerate even further.
It was really shocking to see the 'crappy' old 5570 running this screen at a blazing fast 89 fps at 1xIR and still managing to pump out 65 fps at 4xIR.
There's no such problem with the D3D9 backend (or even the slow-ass OpenGL backend). You can crank up the IR to 4x and still get rock-solid 60fps with VSync + frame limiter enabled (the speed is back to normal: 89fps @ 1xIR).
But D3D11 should perform a whole lot better with these modern cards (significantly faster than D3D9), since they're designed / optimized for D3D11.
HD7750 should be able to handle 4xIR + VSync (D3D11) with ease.
Note: With the old, low-end 5570, D3D11 was performing noticeably faster.
Here are some other (even more shocking) benchmark results :
=====================================================
Dolphin D3D11 BENCH PART I - HD7750 vs. HD5570 (+ some HD6850 results)
=====================================================
MoM @ 4xIR (D3D11), save state of a more demanding (GPU-heavy) scene
-----------------------------------------------------------------------------
HD5570 GDDR3 = 52 fps (same as the HD6850)
HD7750 GDDR5 = 43 fps (!)
SMG1 Observatory @ 2xIR (D3D11):
----------------------------------------------
HD5570 GDDR3 = 47 fps (same as the HD6850)
HD7750 GDDR5 = 42 fps (!)
DKCR 'Start Game' Screen @ 4xIR (D3D11) + VSync:
-------------------------------------------------------------------
HD5570 GDDR3 = 60 fps (same as the HD6850) --> http://postimage.org/image/54iqnp4v5/full/
HD7750 GDDR5 = 41 fps (!), even at 1xIR --> http://postimage.org/image/ruhljxim9/full/
======================================================
DOLPHIN BENCH PART II - D3D9 vs. D3D11 performance on the new HD7750
======================================================
MKWii Menu (Single player) @ 4xIR - really demanding part, needs *a lot* of GPU 'juice'
----------------------------------------------------------------------------------------------------------------
D3D9 = 68 fps
D3D11 = 21 fps (!)
FZERO Machine Select Screen @ 4xIR
-----------------------------------------------
D3D9 = 31 fps
D3D11 = 6 fps (!)
SMS (with EFB to RAM) @ 4xIR
----------------------------------------
D3D9 = 31 fps
D3D11 = 17 fps
DKJB Banana Kingdom (end of level banana bunch) @ 4xIR
----------------------------------------------------------------------------
D3D9 = 71 fps (same as the HD6850)
D3D11 = 50 fps (HD6850 = 68 fps)
Is this an issue with all cards in the HD7000 series ?
Is there anyone with a HD7000 series card who could test and compare the difference in performance between the D3D9 and D3D11 backends ?
Emu: Dolphin GIT 3.0-631 (latest revision)
OS: Win7 SP1 x64
Latest GPU drivers: Catalyst 12.4 WHQL (8.96.1) and 12.5 beta (8.97)