[iChiCkeNBuTT]

Well this happens to me too, just because large FPS killing. Low FPS on game startup = Crash. Try disabling some of your other programs like Antivirus, Skype, Browser, etc what use lot Process on your computer.

There is no use of reinstalling SAMP or SA. Its just out of game thing. Try the following above and refresh your desktop several times. If it didn't worked i am sure that you are having Virus that takes lot process from your computer. I had virus does same thing like this.

Good luck.