LCD Display Problem

Hi,

I have bought a new Samsung SyncMaster 2242LNX (or 2243LNX ?) TFT LCD monitor, I have put it on my old ASUS K8V-MX MOBO which has on-board video (VIA K8M800) and Linux uses VIA graphics driver for that.

As long as I work on command-line it works fine but I can't run X. When I run X then whole screen starts to flicker randomly and the quality of X is too poor to look at. I only got quick set-up guide which says 1680x1050 of optimum resolution at 60 Hz, no manual where I can see Vertical and Horizontal refresh rates . Now since I don't have any Vertical and Horizontal refresh rates what to put in /etc/X11/xorg.conf , which requires a range to be specified.

What could be wrong ? My old Samsung 17 inches CRT monitor works fine on it.

My MOBO has PCI and AGP8x slots only, so I am getting ATI Radeon X1650 card. I thought on-board VGA card does not support that higher amount of resolution, so buying this card will solve my problem ?

Bad new for me, there is only one AGP8x based gfx card in the whole computer market, X1650 with 512 MB or RAM and I don't know wheteher it supports 1680x1050 of resolution *specifically*, though the web-site says it supports 4kx4k. I don't know whether it works on Linux or not, Linux is the only OS I use. 2nd, my mobo supports 1.8 volts cards (not 3.3 V).

If the new card does not work then I am blown as buying a new MOBO will make an AGP 8x based card useless, as all new ones have PCI-Express slots , plus new expanses for CPU and RAM too .. ocuh... it hurts ...