A whi­le ago, I wro­te about using a cheap 1080p TV as ex­ter­nal mo­ni­tor on Ubun­tu. That ha­ppens to cau­se so­me weird pro­ble­ms be­cau­se the TV is tr­ying to be smart about cli­pping things, etc (just read it if you wan­t.)

In it I ou­tli­ned a bun­ch of appro­aches that suc­ceed in fi­xing overscan wi­th di­ffe­rent le­vels of suc­ce­ss. He­re's so­me ex­tra de­tail for one of tho­se, se­tting up a cus­tom mo­de whi­ch does­n't tri­gger overscan:

Firs­t, go to http://www.a­ra­ch­noi­d.­co­m/­mo­de­li­nes/ and crea­te a mo­de­li­ne for so­me mo­de that is clo­se to 1080p but not qui­te the­re. How clo­se to 1080p you can get be­fo­re your TV de­ci­des "this is 1080p I am doing overscan" wi­ll va­r­y.

For exam­ple, I can do 1800­x1012 wi­th this mo­de­li­ne and can pro­ba­bly do a bit mo­re:

Modeline "1800x1012_60.00" 151.42 1800 1912 2104 2408 1012 1013 1016 1048 -HSync +Vsync

Then, to ex­pe­ri­men­t, we can add this mo­de to X using xran­dr. He­re HD­MI1 is the ou­tput I ha­ve con­nec­ted to my TV:

xrandr --newmode "1800x1012_60.00" 151.42 1800 1912 2104 2408 1012 1013 1016 1048 -HSync +Vsync
xrandr --addmode HDMI1 "1800x1012_60.00"
xrandr --output HDMI1 --mode "1800x1012_60.00"

I do­n't thi­nk it wo­rks as we­ll as the for­ce-­d­vi ha­ck from the last ti­me, but he­y, I do get HD­MI au­dio, and I ha­ve not seen this des­cri­bed el­sewhe­re using xran­dr.