ok i really want to install SL or even Leo on my Dx4300-15e Amd Phenom II x4 with 8gb ram, i beleive its a southbridge 780G motherboard??

i want to know what s the proper and easy way, lol, of how to install SL on my machine, while leaving windows 7 intact ( too many important stuff on there, and the kids need it too)

i already have a partion ready for the installation, just need the instructions now!! lol, thanks in advance!!