SiGmA, he meant P4 2Ghz. Intel has came a long way since the 8086 2Mhz chip back in the late 70's
As for Linux for OS Here's my view on it. I dont know anything about Linux. Ive installed it a few times on my home PC and played with it for a few days. Couldnt get it to do what I want so I format and reinstalled windows. For those who know Linux, they swear up and down that it's better than WinXX OS. All of my brother's friends who all works as network engineers and administrators first saw my setup, the first question they ask was dude why didnt you use Linux? Let me rephrase. All of those who know how to drive automatics and sticks all swear up and down that stick is better than automatic cuz you can get it to do exactly what you want. You can say it's faster, peels out in 2nd gear or perhaps 3rd gear, gets better gas mileage to name a few. To those who dont know how to drive a stick, what do they do when they try to drive a stick? they stall the engine at the red light, jerky shift between gears, dont know at what RPM to change gear, cant keep their eyes on the road when they shift to name a few. After a few drives the car is all ****ed up and he's gonna hate stick more than ever. See my point?
OBD-II: There are so many PC based OBD-II setup. google it. Ask your self what do you want to use it for? Datalogging or virtual dash? For me is virtual dash. 1st thing I did was do a google search and forum search on obd-ii and bookmark all the PC based obdii setup. I think I found like 10 of them. I lost all the links since I finished my system. I learn that there are 3 obdii protocols Ford uses PWM, GM uses VPW, Chrysler and imports use ISO. I have a Toyota Tacoma so I assumed that I have ISO but as it turned out earlier Toyotas use PWM. I want to use it other cars so I bought one that'll read all 3 protocols. I went back to all the sites and check out their software to see which one is more eye pleasing. If you can program, then it would matter as long as the code is open source. I found one at www.obd-2.com The only bad thing about this one is it wont reset my ECU's error code. If you're using serial to USB adapter make sure the obd-ii scanner has been tested with the adapter. I hope this helps