I was having the same problem (on a gateway laptop) and have just worked out a fix.
I am using minislack .02 but I assume much of the config will be the same.
at console login as root.
then you need to see what the file for your display settings is called so type
hopefully you will see a file
this is the replacement for
IF xorg exists then edit it using vi or whatever you have
then scroll down for ages until you come to a section on the screen. You should see that there are three or four settings stating
find the one that is not # ed out. In my case it was 24.
Then continue scrolling until you find the screen with depth set at 24 (or your number). at the next line it should say
Modes "1024xXXX" "800x600" etc
put a # at the start of this line so that it is commented out.
on a new line. You have now set the default resolution. (You may need a different setting) exit and save in vi ( push : the w <enter> then : q <enter>) and startx
I am recalling all the settings and details from the top of my head so please excuse the lack of complete accuracy. If anything is too complex or whatnot just give me a reply and I will try and copy the exact file contents.