Since installing Slackware on my desktop, i have been trying to install NVidia driver on it, but it always ended badly. I tried to use the 100.x.y version, but the driver is not supporting old VGA cards, which means i have to use the legacy systems. SO i tried to use 1.0-9631 (the driver that works on my laptop) and the installation was successful, but when i logged in to KDE, the fonts were miserable. It was very huge, making the desktop unusable, so i changed the xorg.conf to use nv rather nvidia to use NVidia driver supported by the kernels (without 3D acceleration).
Today, i tried to use another legacy driver, 1.0-7185 and finally it worked. I can logged in to my KDE and the desktop is still normal. Perhaps it's because i'm using an old VGA Card (GeForce 4 MX i guess). Actually i don't need it badly, since i'm not a gamer and i rarely watched movies from CDs. I used to watch movies by streaming via Internet. Well, finally it has been solved.