[CentOS] How to? Set boot up display resolution

I have been given a replacement monitor for my CentOS-6.3 KVM test
platform.  It is an LG E2251 22in letterbox format screen whereas the
unit it replaces was a 17" standard format display.  The console
messages now look as through they were output on Silly Putty.

The display itself displays a message to set the resolution to 1920 x
1080.  I have found references to using the vga option in the
grub.conf file.  However, I can find no comprehensive list of what
value to use.  The references I have found actually say "see the
source code in the Linux kernel tree", which does not strike me as
particularly "user friendly" shall we say.

How do I do this or am I condemned to rubber band output.
-- 
***          E-Mail is NOT a SECURE channel          ***
James B. Byrne                mailto:ByrneJB at Harte-Lyne.ca
Harte & Lyne Limited          http://www.harte-lyne.ca
9 Brockley Drive              vox: +1 905 561 1241
Hamilton, Ontario             fax: +1 905 561 0757
Canada  L8E 3C3