This guide assumes you are using a variant of Chris Dohnal's OpenGL/Direct3D 8 drivers. These detailed steps are for an AMD PC. Intel PC's should only require the frame rate limit
Note that overclocking probably contributes too, but as I haven't touched that I can't comment on it.
Step 1: Cool and quiet
If you have the "cool and quiet" function turned on then UT will not work properly whatever you do with the next two steps. If you have to ask what this is then it probably isn't an issue, but if you want to make sure go to the power saving area on the screensaver tab when you open properties on the desktop and make sure the power profile is NOT set to "minimal power consumption". That's how it works for me anyway.
If you like having it on (I certainly do as it doesn't seem to affect modern games and does seem to have a noticable effect) then you'll just have to remember to switch it back on after.
Intel apparently has its own version of this, but I have no idea what it's called or any other details.
Step 2: Dual-core fixes
At least part of the problem is related to Dual-core processors. This site has a list of fixes for problems related to this: http://www.hardforum.com/showthread.php?t=983781
Despite what it says in the second post fix#1 instantly fixed my UT problems (after step 1 was done), so since it seems to vary I guess you'll just have to experiment in this regard (since that post was made last year, perhaps fix#1 has since been updated and that's why it works?)
Edit: This seems to be a newer version of the optimiser and a working link (AMD only and Dual-core only): http://support.amd.com/us/Pages/dynamic ... ItemID=153
Note: While it sounds obvious, just in case; DO NOT install the dual-core optimiser if you have three or more cores! The other fixes here should hopefully be enough.
Step 3: Frame rate limit
If you have got steps 1 and 2 done successfully then UT's performance should have at least a small degree of normality when you open it, but there are still some final ingame tweaks before it is fully fixed. In UT's advanced properties (Oldskool lets you access them easily from the menu). On the OpenGL settings in renderer set the "frameratelimit" option to somewhere between 100 and 200 (I currently am using 100, as 200 still gave the gameplay a slightly unnatural feeling for me). I don't know about the equivalent option for Direct3D 8. At this stage, Vsync may work as well, but I haven't tried it.
When I tried this before the other two I got strange performance glitches even in the menu, so leave this step for last.
There, now UT should be back to how it normally feels.
Edit 2: Another fix if speed issues persist on Vista or Windows 7 after the above:
Waffnuffly wrote:I found something else interesting on Vista here at work. If you right click the UT exe, go to Compatibility, and then put a check next to "Disable Desktop Composition," the game no longer runs in turbo mode super speed.
Edit 3: If you're having obviously laggy mouse movement and other issues try this:
Mman wrote:For mouse weirdness (in Windows 7 at least), try this http://donewmouseaccel.blogspot.co.uk/2 ... n-fix.html
Just download the fix and run the registry file for whatever DPI your computer is at (probably 100%) and restart. Newer versions of Windows have a weird mouse acceleration curve that is very noticeable in some games (and older Unreal engine games seem to be particular offenders). The fix smoothes it out, which might fix your issue, and, either way, it will improve general mouse consistency in games.
Turning directinput on/off in the game options may also help