Mouse lag caused by Anti-Aliasing

I recently found out that my immense mouse lag in games - such as Company of Heroes and Left 4 Dead - is caused by turning on AA. The performance seems unaffected by the AA, but the mouse lags like hell.

Naturally, I'd like to be able to turn it on, especially since L4D looks kinda shoddy without it.

Any suggestions for finding out what the correlation is and how to fix it?

 

As far as I know, there is no correlation between the two. AA can cause mouse lag if makes your FPS fall below your screen refresh rate, usually 60FPS. Vsync however can/does cause mouse lag, are you sure you aren't talking about Vsync?

 

AA. Only parameter that I've changed, when the mouse lag appears. Disabling it again removes the lag.

No VSync enabled.

 

Your computer isn't powerful enough to run AA during a game. AA is more taxing than most other graphic options so it gives you the most lag. Just turn it off.

 

thats odd, is AA only causing mouse lag and not real lag? is the mouse lag directly related to real lag or is it indenpendent. as far as I know AA does not cause mouse lag

 

How do you know its mouse lag and not the actual game struggling?

You can only say its mouse lag is if you have a visual mouse pointer and thats the only thing thats lagging.

 

turn off AA and raise the resolution as much as you can.

 

I would bet his gpu isnt powerful enough for the settings he is choosing, and thus causing drops of fps that make the mouse appear to lag.

 

Turning the settings - except AA - all down still yields the same result.

 

Bad drivers? .. one of the drivers i used used to stutter if i set the AA higher than 4x. Though it runs perfect on 2x

 

System specs?
Does it happen in any other games?
Any difference when you enable AA through your control panel instead of in-game?

Enabling AA could be causing those games to eat up more vram than is available on your gpu. Your gpu will then borrow system ram which, depending on the game, can cause slowdown or visual glitches, ie. textures appearing or dissapearing out of nowhere, while maintaing a similar framerate.

 

Ah, I love that. Heaps of my friends complain of "keyboard lag" or "mouse lag" when trying to run UT3 or BioShock on their ancient notebooks.

 

Dead Space's V-sync causes mouse lag in the menus.

 

why don't you tell us what you're system is?

9200m gs?

trying to turn on AA with a 3450?

 

It seems like he has a Thinkpad T500 with an ATI 3650 Mobility, and he has had quite a bit of trouble with it but no one has helped him.
http://forum.notebookreview.com/showthread.php?t=311378

I'm inclined to believe that there's an actual problem with his hardware or drivers, rather than how several people here are just speculating that his computer is not capable of handling AA.

For reference, my 8600M GT is able to handle L4D at 1280x800, all settings high but shaders, and 2xAA and still maintain a constant of around 50 - 70.

 

Great, my post got lost. One more time ...

Some games experience lag - the menu of BioShock does, but Civilization IV, in-game and in-menu, is fine. I don't have a lot of games to test. I'm running the game on this laptop.

I'm running Lenovo's own newest driver for my Vista Ultimate 64 - I haven't managed to install a non-Lenovo driver. Secondly, I can't benchmark using Futuremark's tools, so if anyone knows the console command for benchmark/FPS is in Left 4 Dead / Source games, let me know. That way we could make sure that crippled performance is the culprit, but I doubt it.

As I recall, Half-Life 2 ran with no hiccups with the max settings, so Left 4 Dead should be no different - I'm running it at max except for the AA. AF is only at 2x or 4x, though.

Enabling it in-game or by CCC makes no difference.

EDIT: For the sake of the performance discussion, BioShock and Civ 4 run at max settings, also. BioShock's performance is probably not at 50 FPS, though.

 

ATI gpu's arn't so great with AA, or at least havn't been in the past, and if it's a DDR2 card then it'll probably be even worse.

The first thing to do if this is a serious problem for you is to try a different driver, second would be to re-install and re-update the game.

 

HL2 is based on a much older version of the Source engine. The Source engine has since been updated several times over the years. L4D and TF2 require a lot more power to run than HL2 does.

 

Why dont you just post the specs of your laptop instead of telling us what is and isnt running?

 

T9600(2.8GHz), 4GB RAM, 160GB 7200rpm HD, 15.4in 1680x1050 LCD, 256MB ATI Radeon HD3650, CDRW/DVDRW, Intel 802.11agn wireless, Bluetooth, Modem, 1Gb Ethernet, UltraNav, Secure chip, FPR, Camera, Intel Turbo Memory, 9c Li-Ion, WinVista Business 32

 

I did. It's in the aforementioned link. But the specs have been posted once by cathy, so I won't c/p them.

 

turn shaders down to medium.

problem solved.

 

That did the trick! Fantastic. This makes much more sense in terms of the shortcomings of the graphic card, though I am not in a position to say what caused the shader and AA settings to create the conflict.

Thanks, all.

 

Don't tell me you had it set to D3D 10?!

Nice catch chef XD

 

I didn't see any specific notices about DX/D3D 10, but if that's what High/Very High Shader settings in Left 4 Dead means, then I guess I did. I just thought they'd write it explicitly, like they do in other games.

 

In company of heroes?

It really kills performance in that game.

 

Left 4 Dead. Haven't tested CoH yet, but I know about the DX10 woes there. I didn't install the DX10 DVD, either.

 

Umm, actually its a conflict between the source engine and AtiHotkey Poller

Go to Control Panel>Administrative Tools>Services, right-click on AtiHotKey Poller and in Startup type choose "Disabled", restart and enjoy mouse lag free gaming.

It seems that the ati tool listens for keystrokes and runs them through its recognition software before handing them to a game. This fixed my mouse lag probs in L4D.

 

The only ATI service I see is Ati External Event Utility.

 

you didn't really have mouse lag. it was a framerate issue. having the shaders on high absolutely kills performance in L4D.

as the performance of your game drops, the first thing you will lose is the quick twitch-like responsiveness. as performance continues to drop, you will eventually lose perceived smoothness of motion.

but there is a performance range where you do not have twitch responsiveness but you still perceive smooth motion with your eyes.