robert91 :
No response so I went and bought the 2560 x 1440 monitor, and YES, the HD 2500 graphics card DOES support the 2560 x 1440 resolution. You MUST use a Display Port to Display Port cable. A Display Port to HDMI only showed the 1080 x 1920 max resolution.
funny, i was just looking to answer this very same question! what are the odds.
so i guess it'll be able to drive this screen: LG 25UM58-P 25" Class 21:9 UltraWide Full HD IPS Monitor 5ms 2560 x 1080 75 Hz Refresh Rate Flicker Safe Black Stabilizer and On Screen Control w/ Screen Split 2.0 HDMI.... ah but wait... screen only has HDMI connectors!!!!! WTF???!!! i knew it was too good to be true.. goddam it.
EDIT: actually, i did some more searching and found this: 'A dual-link DVI connection (as opposed to single-link) can handle 2560x1440 at 60Hz, but not 3840x2160 (which is the typical; 4K resolution).'
here: http://www.pcadvisor.co.uk/how-to/pc-peripheral/how-connect-4k-screen-pc-3634369/
so, since i'm going for a cheapo Dell Optiplex 7010 system (obviously NOT for gaming) which has 2 DVI ports in the back, and IF those ports are dual-link, then the integrated Intel HD2500 should be able to drive the LG screen when using a DVI to HDMI 2.0 adapter.
EDIT 2: further research confirmed that you could get a DP to HDMI Active adapter to drive a screen up to 4K@60Hz, BUT DP must be vs 1.2. here:
https://www.startech.com/AV/Displayport-Converters/dp-hdmi-2-adapter-4k~DP2HD4K60S