yes you could run gta4 .need prove. all you need is q8200,4gb ram,9500gt to run it. ps3 is running 7900gt on 640p on their system so its possible to run it~! you have to update ur driver and game.so patch it up to 1.3 version to fix fps. if you want to run it to xbox 360 graphic(which is 720p).trust me it work. here is the setting.also i found that when you run texture high.you get more fps.its wierd but its true. anywayz, here
http://www.youtube.com/watch?v=SjofL8hoLr4
also when i go outside the game. i get 30 to 45 fps. believe me.it work.
rockstar did a terrible job porting it to pc. i use commandline to fix everything.
Statistics
Average FPS: 34.69
Duration: 37.02 sec
CPU Usage: 85%
System memory usage: 67%
Video memory usage: 100%
Graphics Settings
Video Mode: 1280 x 720 (60 Hz)
Texture Quality: High
Texture Filter Quality: Highest
View Distance: 30
Detail Distance: 40
car :26
shadow:0
Hardware
Microsoft® Windows Vista" Ultimate
Service Pack 1
Video Adapter: NVIDIA GeForce 9500 GT
Video Driver version: 185.85
Audio Adapter: Speakers (High Definition Audio Device)
Intel(R) Core(TM)2 Quad CPU Q8200 @ 2.33GHz
1)update ur card to the latest.
2)update ur gta 4 to the latest
3)to get awesome frame rate on gta 4.
4)start gta4
5)setting resolution to 800x600. set the graphic just like me. this is xbox 360 and ps3 graphic setting. trust me. i got it on my console too.
6)save it and quit the game.
7)now right click on gta 4 icon.
8) go to properties.
9) look for taget section and type this in. -width 1280 -height 720 -availablevidmem 0.7914979757085020242914979757085 -novblank -norestrictions -dx9
10)it should look like this.
"C:\Program Files\Rockstar Games\Grand Theft Auto IV\LaunchGTAIV.exe" -width 1280 -height 720 -availablevidmem 0.7914979757085020242914979757085 -novblank -norestrictions -dx9
11)now start the game and you will have awesome fps and game without lag! need help.comment me and i reply back also i found that when you turn off hd off.you lose framrate by 5 point.i recommand to leave it on. it doesnt matter if you have to buy super gpu to run it high setting. its how they port the game.