***MAJOR PERFORMANCE TWEAKS FOR DOOM 3***

[xSkyDrAx]

This was quoted from someone at gamefaq forums, okay yea a lot of them suck but this is the real deal.

Originally posted by: Biggs6575
I tried this and Im now runnig at 1280x1024 compared to 800x600 at the same settings.

"As all of you who allready have this game recognized the game is very slow even on new Computers.

I found out the reason for this and the solution to fix this problem.

As you already know after installation the game consits only of the doom3.exe and some .PK4 files. Those PK4 files includes the entire game (sounds, videos, textures etc.) in high compressed form.

Normally those files were decompresse during the game.

But this exactly is the problem. Even new CPUs are not able to decompress those files while running the game with good peformance and therfore the game runs very **** also on new computers. I don't know if the develpers of ID-Soft was just too stupid to think about this or if they have an agreement with some hardware manufacturing firms.

How to get around this problem:

It is very simple. Go to your Doom 3 installation directoy and get inside the folder "Base". There are some .PK4 files you have to open each of them with WinRAR 3.3 and extract their entire contents to the Base dir in you Doom 3 installation folder (replace all files if they are any duplicates). Now you have to delete all .PK4 files in the Base folder to prevent the game to use those compressed files agian.

Now the game starts and runs mutch faster!!!

Have fun playing Doom 3!!! "

-karlmueller

I've tried it and it works. I can even play at 1024x800 at medium w/30-60 fps depending on where and never dips below 20 compared to play at 800x640 at medium and averaging around the 30's-40's with dips below 20.



*Cliff Notes*
Use Winrar to decompress pak000 through pak004 to your Doom3\base folder. Then rename the origional pak000 - pak004 files and store them somewhere else (this is cause the tweak has some problems with online play so it's good to back the origional .pak files.)

 

[zodder]

I might have to check this out. Thanks.

 

[spherrod]

Definitely worth a try - Cheers! :beer:

 

[Bumrush99]

another reason to waste hours tweaking instead of playing the game.. I can't wait

 

[ugh]

Uhh... How much space does it occupy once it's fully un-RAR-ed?

 

[Bumrush99]

Originally posted by: ugh
Uhh... How much space does it occupy once it's fully un-RAR-ed?

Who cares??? It can give you 1.222 extra FPS after running the timedemo 12 times!!!

 

[xSkyDrAx]

It's about 2+ gigs after the entire unrar. And you cant test the tweak with the timedemo because that doesn't really have anything to do with loading and decompressing the files so you wont see a change in the timedemo.

 

That's going to screw up updates if you delete the orginal pak files. Keep them backed up somewhere and replace them when you update then repeat the process after the update.

 

[notfred]

Originally posted by: xSkyDrAx
It's about 2+ gigs after the entire unrar. And you cant test the tweak with the timedemo because that doesn't really have anything to do with loading and decompressing the files so you wont see a change in the timedemo.

Uh, the timedemo works exactly as if you were playing the game. If files need to be loaded into memory for the game, they're going to need to be loaded into memory for the timedemo.

 

[Czar]

market for later checking

 

[Regs]

Originally posted by: notfred

Originally posted by: xSkyDrAx
It's about 2+ gigs after the entire unrar. And you cant test the tweak with the timedemo because that doesn't really have anything to do with loading and decompressing the files so you wont see a change in the timedemo.

Uh, the timedemo works exactly as if you were playing the game. If files need to be loaded into memory for the game, they're going to need to be loaded into memory for the timedemo.

That's what I was thinking. I would just guess it may just shorten load times if even that.

 

[So]

The benefits sound dubious at best...anyone try it yet? (at work so I can't, ATM).

 

[JeffreyY]

id has been using pak files since quake 2 days (or maybe even earlier) and I've never heard of tweaks like this. I'm skeptical, but I guess it doesn't hurt to try.

 

[Looney]

I highly doubt uncompression is done on the fly anyways... and is done while the level is loading, which is why we have such long load time. So no, i don't think this will help, maybe for level loading, but i can't see how this would help during gameplay.

 

[Lonyo]

Time to find out if it does help.
I will report back.

 

[Johnbear007]

Originally posted by: dwell
That's going to screw up updates if you delete the orginal pak files. Keep them backed up somewhere and replace them when you update then repeat the process after the update.

I will have them backed up somwhere. On the cd

 

[Lonyo]

I have tried this out, it gave me ~0.15 fps extra. Not really worth it.
However, not sure if it's related to this, but I did notice that when I exited Doom 3 the desktop was VERY responsive and quick to use. Less caching of files so less to clear when you exit Doom 3?

But really, no difference

Before unpacking:
44.6 and 44.4 fps

After:
44.8 and 44.7 fps.

(Cache thing set to 128 though, from the default 20, that might also effect it). First run through of timedemo was actually SLOWER than before.

OK, I set cachemegs to 256 and the first run was 39.6 and subsequent runs were 44.9 and 44.7 fps.
cachmegs above 128 made no real difference, and neither did unpacking the pk4 files, but I got an extra 5fps from setting cachemegs to 128 up from 20 default.

EDIT: Currently downloading Catalyst 4.9 betas and I will try them eventually, see how they help my 9800 non-pro.

 

[Smilin]

Lonyo checked it out before I could post.

I declare shenanigans on this tweak. It's BS.


A little something to know about modern video games: If you can't fit all the textures into the video card it will texture thrash trying to read them across the AGP bus. It will bottleneck going to and from main memory no matter if the texture are compressed or not.

 

[Lonyo]

OK, I've finished doing all I think I'm going to do for now.

My Doom 3 tweaking results, all done with the same system and only the changes as noted:
AMD Athlon XP-M 2500+ @ 2266MHz (17x133)
1GB (2x512MB) PC2100 DDR
Sapphire Radeon 9800 non-pro overclocked to 403MHz core 316MHz (632MHz) RAM
Onboard sound (Realtek)
ABit NF7 (non -S) v2.0
1024x768 @ medium quality
"timedemo demo1" at console (no quotes)

Test 1
cachemegs 20
Cat 4.7's
Main runs: 39.1 and 39.1 fps

Test 2:
cachemegs 128
Cat 4.7's
Main runs: 44.6 and 44.4 fps

Test 3:
cachemegs 128
Cat 4.7's
pk4 files unrarred to Doom3\base folder
Main runs: 44.8 and 44.7 fps

Test 4:
cachemegs 256
Cat 4.7's
pk4 files unrarred to Doom3\base folder
Main runs: 44.9 and 44.7 fps


Test 5:
Cat 4.9 betas (from Guru3D.com - says 4.8 in Cat control panel?)
cachemegs 256
pk4's unrarred
Main runs: 47.0 and 46.9 fps.

Results:
Unrarring pk4 files did nothing much escept take up disc space
Changing cachemegs from 20 to 128 did wonders, but anything above that showed no effect, I'm not sure what lower values may do, othes have found cachemegs to have no real effect.
Using the Cat 4.9 beta from Guru3D over the Cat 4.7's improved performance.

After all tweaking, frame rates improved: 20%
With no additional overclock, or any different components, this was all using my existing system and I got 20% extra performance out of it, for free.

Hope this helps people out.

 

[leeland]

how do you go about changing the cachemegs ??? and a better question, what is it ?


Thanks


Leeland

 

[Lonyo]

To change cachemegs:

Doomconfig.cfg file: (In xxx\Doom3\base\ folder)
seta image_cacheMegs "xx" (Default 20)
To change cachemegs setting.

I have no idea what it is, someone posted it as a tweak, and it worked for me, there is another thread about it somewhere.
Make xx something like 128 or 256, I found 256 didn't help too much above 128, but it didn't affect the rest of my system either, it's very responsive when I close Doom 3.

 

[bigrod]

Should cachemegs be set to the same amount of memory that your video card has? Kind of like AGP apeture in the BIOS?

 

[Andvari]

Originally posted by: bigrod
Should cachemegs be set to the same amount of memory that your video card has? Kind of like AGP apeture in the BIOS?

My AGP aperture is set at 128 megs, whereas my Radeon 9800 Pro has 256mb. Should I up the aperture?

 

[Corey0808]

I thought that setting in the BIOS wasn't used much anymore. I thought that it was used when the the ram on the video card is all used up. Not sure though

 

[CrazyHelloDeli]

I tried the the "Cache" tweak and my game went from semi choppy to very very smooth. I have a 3500+, 1GB RAM, and 6800 GT OC.