Input lag question

RetroArch Windows devices
#1

Is input lag affected by CPU performance?

I have an old computer with a core 2 duo @2ghz with 4gb ddr2 running win XP 64bit. It’s hooked up to a sony PVM CRT monitor. I have noticeable input lag with Retroarch.

However, my i5 3570k system with Win7 has no perceptible input lag when running Retroarch on my LCD tv with game mode activated. (19ms latency in game mode)

I have compared the two systems to an actual SNES on a CRT and the i5 on the LCD actually feels very close to the real SNES in terms of lag while the core 2 duo system on the crt is much laggier. Is there any explanation for this?

#2

Input lag is 99% caused by the video drivers internal buffering and queueing (which is highly unpredictable from an applications point of view). Unless you’re getting sub 60-fps or anything, the CPU speed should not matter one bit. Try Hard GPU Sync with 0 or 1 frame, it usually helps a bit, especially on Windows.

#3

It appears to be caused by crt_emudriver, a hacked ATI driver that allows low resolutions for CRT use. when I uninstalled it and installed the lastest official AMD drivers for my HD4350 the lag was gone. This is unfortunate since I need those drivers for CRT usage, but now that I have a low lag TV and it looks very nice with CRT shaders I might just put the PVM in storage.

#4

Hah. Aren’t those drivers hailed for their uber-low video latency? :stuck_out_tongue:

#5

well to be fair I don’t have any noticeable lag in groovymame, but this driver and retroarch don’t seem to get along on my system for some reason.

#6

quick update. installed crt emudriver windows 7 beta and the lag is gone. :slight_smile: