since the ps3 isn't out yet, its pure speculation to try to figure out what PC resolutions it will accept. however, for guaranteed 720p compatibility, you'll need a monitor that can accept a high-def TV signal either via HDMI (or DVI w/HDCP) or component inputs. (i wouldn't trust plain DVI on a monitor due to copy protection.)
most lcd tvs are 1366x768 so scaling is commonplace and to be expected. (note, scaling is different than stretching.) however, most monitors are 16x10 instead of 16x9 so there may be some stretching but you'll have to decide if its suits your personal taste.
i suggest you look at these monitors:
samsung 215tw, 20" 1680x1050, about $470
http://www.samsung.com/Products/Monitor/LCD_Digital/LS21DPWABXAA.asp
westinghouse lcm-22w2, 22" 1680x1050, $400 at BB
https://www.westinghousedigital.com/pc-60-3-22-widescreen-monitor.aspx
both accept TV high-def inputs.
Ok, so I'm looking for a computer monitor to use for my PS3 in my room.(Once I get one.... a PS3 that is, not a room)
Don't need a big one, I'm just looking at things around 17-19'' widescreen. Most of the ones I've seen have a resolution of 1440 x 900. I've been told this will run in 720p, but I've also heard that there will be a fair amont of stretching going on, due to not running in its native resolution.
What max resolution will run 720p the best? I'm basically looking for a monitor with a native resolution to run 720p well without any major stretching, etc, and 1080i/p are most likely out of my price range as well.

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