Can only run 680x460 and 16 colors, why?

I've had some spyware problems that I've fixed now, but now I can't get my computer out of 640x480 screen resolution and 16 colors. Not 16 BIT colors, just regular 16 colors. This computer is 7 years old or so, but it used to run on 800x600 and 16 bit colors, but now whenever I try to apply those changes, it doesn't stay. Anyone know why? It's a 333mhz computer with 3D Blaster Riva TNT graphics card. Anyone able to help me out please?

 

make sure you have your video drivers installed and possibly monitor drivers depending on your monitor.

 

Romial--

This is a "hardware" question

Welcome to Major Geeks

P.S.: they are going to want to know your details, like, machine, operating system, along with the video card you stated

Good Luck