horizontal bands on pc screen

Is your monitor cable screwed tightly to the back of the computer? My first instinct is the monitor is going bad.

KOGi L4BX 14.1-inch LCD Monitor
CompUSA Price: $219.99
after rebate(s)*

Remove any drivers for your current grafics card and ahut down and install new card and then the drivers for it.

Well most likely, unless you made a special order for a hot-rod video card for gaming, the video chip is on your motherboard. If your computer is still under warentee, contact the manufacturer. If not, just go purchase another one. They are cheapthrow-away items. Before you spend money I would be comfortable if you would try another monitor on your computer and if possible, try your monitor on another computer to see if the problem follows the computer or the monitor. Find a buddy who hasa computer and try that with them. It doesn't look like a driver issue for a bad driver would just crash your system. Try that and good luck.

The previous answer that was rejected would have been my first guess, which is all anyone can do with out more information but I'll try.
1. Connect the monitor to another PC if possible
to see if it works. If it still has the same
problem the monitor is probably bad or
possibly check/reset the monitor controls to
factory default settings. If it works see 2.
2. After ruling out the monitor as being the
problem source re-connect it to your PC and
use a bootable DOS floppy to start the
machine with a MS-DOS command prompt. If you
do not see the banding and the display appears
normal you can rule it out as the problem
source and move on to 3. If the horizontal
bands still appear it is probably the display
adapter which may need to either be re-
seated in it's expansion slot or replaced
unless you have onboard video in which case
you will have to disable it first before
replacing it with an add-on display adapter
card.
3. If you have ruled out both the monitor &
display adapter as the problem source the only
other possibility I can think right now is the
problem lies within the operating system. If
you are using Windows be sure to remove the
boot floopy if it is still in the drive from
step 2 and start Windows in "Safe Mode" which
is done differently depending on the version
of Windows you are running. After starting
Windows in "Safe Mode" enter Windows Device
Manager and remove all instances of display
adapters & monitors found. Close Windows
Device Manager and re-start Windows normally.
If after all this you still can not identify/fix
the problem feel free to reject this answer and I'll try again. Good Luck!