Severe button lag in some emulators...

[ahofle]

Greetings.  This weekend I upgraded my MAME cab computer from Win98 to XP.  MAME and MESS worked just fine after the upgrade.  However, a couple emulators (NES: FCEUltra and SNES: ZSNES) exhibit severe input lag (like a second or two after I press a button, the emulator reacts).  Any ideas how to fix this?

[2600]

We need more information otherwise people tend to make gross assumptions.

[ahofle]

Sure, I'll give it a try.
For example, if I fire up Super Mario Bros on FCEUltra, when I press 'right' on the joystick, it takes a second or two for Mario to move right.  Same with every other direction, jumping, etc.  The same keypresses provide instantaneous freedback in windows and even MAME, however.  I'm using an IPAC4 in USB mode if that matters.  This all started happening right after I upgraded windows.     I would have assumed it was just FCEUltra, but I get the same exact behavior in ZSNES.
Let me know any other information which would be helpful.

[2600]

Decent PC? (Just making sure you aren't trying to run XP with 16MB of RAM)
Because this your cab PC, I'm assuming you aren't running any other apps in the background. True?
Did you upgrade to Xp or clean install?


Have you tried a keyboard or the IPAC in PS/2 mode?
Are you using a USB hub? 1.1 hub or 2.0?
Is there anything else attached to the USB bus?

[ahofle]

My PC is only decent, but should be enough for XP: Athlon XP 2000+ with 512 Meg RAM.  I performed an upgrade instead of a clean install because I was lazy and didn't want to reinstall things like Winzip, etc.  Maybe that was a mistake (although everything else seems to work peachy).  I turned off a few unnecessary services, but I really need to thoroughly go through and strip it down.  Good call on the keyboard in PS2 mode, I'll try that when I get home.  I am using a USB hub but I'm not sure if it's 1.1 or 2.0 (can't remember).  In addition to the IPAC, I also have an Optipac attached to the same hub (which seems to work fine).  I'll check some of these suggestions when I get home.  Thanks for the help.

[2600]

Also, check if your PC supports USB 2.0.  If you don't know how:
Go to Device Manager
Click on USB device Controllers (at the bottom)
See if there is entry for Enhanced USB Controller or EHCI


My current money is on the following.
1. USB 2.0
Solution: Either don't use the hub or turn off the USB 2.0 in the BIOS
2. The USB hub
Solution: Your USB hub is really crappy.  Don't use it or get a new one.

[ahofle]

OK thinking back I'm pretty sure the motherboard doesn't support USB2.0.  I think you are right on with the hub being the problem.  I now remember having some issues at first with windows seeing the IPAC and Optipac.  I plugged the hub (powered by its own adapter) into a different USB port on the computer and it magically started working though so I never even considered it.  Guess I need to get on newegg and find a hub that doesn't suck.  I'll report back.

[2600]

Don't throw out the hub yet.  Make sure they work fine using the onboard USB connectors first.

[ahofle]

Well I believe I have ruled out the USB hub as the problem.  I tried with a PS2 keyboard, as well as straight connection to the motherboard USB inputs -- all exhibit the lag.  I think the problem has something to do with video believe it or not.  I was able to get rid of the problem in FCEUltra by selecting <none> under the 'sync method'.  When I turned double buffering or VBlank back on the lag came back.  Bizarre.  I guess I'm stuck with screen tearing to avoid the input lag.  I haven't found any setting in ZSNES that gets rid of the lag however.   I neglected to mention this but I did change monitors during the upgrade (from standard CGA arcade monitor to betson multisync).  I have no clue how that could cause this though.  

[Howard_Casto]

This sounds like a direct-x issue.  I've ran into sluggish response before due to bad drivers/and old version of dx installed/ ect. 

So I say look at the software end of things and try turning off options like "use direct input" in your emus. 

[ahofle]

Well you are right about it being the software.  I just upgraded ZSNES to the latest version and now it all works!  Thanks for the help guys!