So, you go to PCLinuxOS Control Center >> Hardware >> Configure Video Card.
Then you select the right video card (I hope you succeeded in that part; could you give us
the brand & model of video card in the system, and what
the driver you selected?).
After that, click on the button next to monitor, and choose "Generic": click on the wanted resolution...
Do not stop here; press OK and next, click on the button next to resolution
=> select drop down box, choose other, and click again on the drop down box: click again on the desired resolution (and if you want to change the color mode, it's the moment too)...
Then have a look at the options (if you're not sure, post here which options are activated and which aren't)
After changing all those settings, press "OK", and log off and on again (or do a reboot).
Let us know how it goes (or if you already tried it this way, answer then the first question please