Help with MC

So I found a old ass computer and I am gonna buy a gaming computer this summer but in MineCraft If I put my version past 1.7.2 it just goes all black screen and I can hear the music,clicks, etc. but the screen is black. I am goign to be a mod on a server but I cant since its BukkCraft 1.7.9 and I cant get 1.7.9 cause its black screen. PLEASE HELP!!!!

Try Using Optifine to help you with this problem

Optifine can be downloaded at optifine.net

You can change the settings in .minecraft folder without launching the game