Thanks for the DDraw fix! So much smoother now. :)
Also, I don't know if anyone else has had this problem, but with the hi-res pack I couldn't go anywhere in the radscorpion cave. I could move around the screen, but I couldn't scroll to go anywhere else other than the first bit you c an see. It appears to be wrong numbers put into an .ini file.
If you have this problem, go to the "f1_res" folder and open "map_edges_F1.ini" - in it you'll see the edges mapped out by number for each section of the game. Here is what I have for the Caves section:
NAME = CAVES
ELEVATION = 1
LEFT_EDGE = 1568
RIGHT_EDGE = 2540
TOP_EDGE = 1840
BOTTOM_EDGE = 1532
I'm not sure if these are accurate, but they worked for me. Have fun!

Thanks for the fix. Was wondering why Fallout 2 ran perfectly with the high resolution patch but Fallout 1 ran like shit.

I'm playing it on my laptop on the train, hence the integrated graphics.

Allow me to join the chorus of thanks. It was depressing watching an 11 year old game barely run on a modern computer.

I have it installed but haven't played it, so I am happy to have found this before hand. I have already renamed the file and cant wait to get back in the world

The high resolution patch doesn't seem to work for me. I've tried to set the resolution as 800x600 and 1024x768 but the game uses whatever my current desktop resolution is.

You have to set AUTO_SCRN_SIZE = 0 in f2_res.cfg
That will force Fallout to use whatever resolution you have chose.

Removing the .dll worked as far as speed goes for me too, but without it I get a different problem and that's that the screen goes black. (which gets removed by the player char. and moving the cursor around like an eraser, but it reappears within short again)
I tried different resolutions and compability modes to no avail, unfortunately it does lag, but I prefer that to not seing anything at all about once/30 secs. (and will try making a profile with everything to do with graphic acceleration turned off)
Just a warning that the removal of the file might not always work well...
Edit:
I have a Radeon 2600XT
Update:
I found a solution to my problem with timeslips patch:
http://timeslip.chorrol.com/sfall.html
Using his ddraw.dll I get the speed I got without the original but the blackening of the screen is gone.
I had to change graphics mode to 4 in ddraw.ini that came with it though, which causes a bit of pixelization of the movies, but I can easily live with that. :)

Renaming the ddraw.dll file fixes my speed. Though now I'm having the same bit depth (?)/color problem I was having with Fallout 2

Whenever I use a resolution other then my desktop's resolution or the game's standard resolution I get an error message that says "Error initializing video mode 640X480"
Edit: I can't use any other 16:10 resolutions. 4:3 ones work fine.

I got that message when I put some ddraw.dll that I downloaded in the fallout folder...
Did you try this? :
http://timeslip.chorrol.com/sfall.html
I don't know if it'll help but it may be worth a shot, it's just to delete it if it doesn't work, so... :)

Nope doesn't fix it.

Just wanted to confirm that renaming ddraw.dll fixes the slowdown that the Fallout 1 High Resolution patch creates.

Aye, it does. Good stuff.

Got a new problem now with color.
Colors are acting strange, patches of 8-bit looking stuff. It did it once and then wasn't doing it, but now it always does it.