Need help with my xbox 360 slim arcade and pc monitor

[alex217c]

I've got my xbox 360 connected to my 24 inch benq 1080p monitor via vga cable. the xbox display setting is set at 1920x1080 but when i play games like assasins creed brotherhood or need for speed hot pursuit i see ALOT of jagged edges. almost looks as if i was playing at much much lower resolution... I remember seeing xbox 360's at eb games and some places and it looked alot more clearer and crisp. is there a problem with my monitor and xbox compatibility? would getting a HDTV solve this problem?

[MonsieurX]

A vast majority of 360's are 720P native(or even less) upscaled to 1080P.

[sleepyguy]

also cause your u r sitting close... look at your tv close and you'll see all the jaggedness and blurriness.