Page 1 of 1

Emulator performance w/ FreeSync

Posted: 12 Jul 2015, 08:47
by BlackGuyRX
Anyone knows how well emulators like RetroArch and vanilla MAME & MESS perform with FreeSync? I see stuff all over the net about how wonderful G-Sync is in this feild, but see next to nothing regarding FreeSync.

Re: Emulator performance w/ FreeSync

Posted: 13 Jul 2015, 02:59
by lexlazootin
It would perform the same as Gsync.

Re: Emulator performance w/ FreeSync

Posted: 13 Jul 2015, 20:53
by BlackGuyRX
lexlazootin wrote:It would perform the same as Gsync.
Exactly the same? I've read FreeSync has some issues compared to G-Sync.

Re: Emulator performance w/ FreeSync

Posted: 22 Oct 2017, 07:37
by Pilaffo
BlackGuyRX wrote:
lexlazootin wrote:It would perform the same as Gsync.
Exactly the same? I've read FreeSync has some issues compared to G-Sync.

Hi,

for my experience i can confirm that Freesync works, i bought the Asus G245H for a Mame use as far as emulation is concerned.

tested with Mameui Plus 0.168 with Direct3d and with scalers (scale2x, scale3x, hq2x etc.) or with Hlsl and all games between 40hz and 75hz (the variable refresh of the G245H) worked perfectly without stuttering and at their native speed as if they were on the original arcade counterpart

Re: Emulator performance w/ FreeSync

Posted: 22 Oct 2017, 09:36
by RealNC
BlackGuyRX wrote:
lexlazootin wrote:It would perform the same as Gsync.
Exactly the same? I've read FreeSync has some issues compared to G-Sync.
Some monitors have issues, yes, but they shouldn't affect emulation. The issues are sub-par overdrive implementation (causes ghosting), lack of low frame rate compensation (causes VRR to not function at low FPS, usually near 30FPS), and too narrow FreeSync range.

The ghosting doesn't affect emulation for obvious reasons. The lack of LFC would only affect emulation if a game would run at low frame rates. But arcade and retro console games always run at 40+ FPS. Usually 55+. So there should be no issues, as long as the monitor has a wide enough FreeSync range. A supported range of at least 35Hz-80Hz should work fine with any emulated game.

So if you get a monitor with a wide FreeSync range, everything should be fine.

Re: Emulator performance w/ FreeSync

Posted: 24 Oct 2017, 12:11
by Chief Blur Buster
No matter what you do, make sure you have VRR of at least 75Hz for use with 60Hz emulators.

You need Hz headroom for low emulator lag, so you can't use 60Hz VRR to get low-lag 60Hz emulator use. So to get that headroom, you need Hz limit above 60Hz for pleasantly low-lag 60Hz emulator use. That successfully allows the emulator to have 60Hz perfect fluidity motion without the lag of "VSYNC ON".

So a VRR monitor 75Hz or higher, minimum. Either a FreeSync monitor (for AMD) or GSYNC monitor (for NVIDIA).

Also, there's a secondary effect: The higher the max Hz, the lower lag gets. 144Hz and 240Hz VRR has less 60Hz emulator lag than 75Hz VRR. This happens because the refresh cycles appear quicker. During variable refresh rate operation, a 60Hz "refresh cycle" always finishes refreshing in 1/144sec at 144Hz (or 1/240sec at 240Hz) even though it's refreshing only 60 times a second. This is because of faster scanout of refresh cycles: The scanout is at a constant velocity on a VRR monitor in VRR mode -- only the time interval between refresh cycles varies.