Hello,
What matters is the pixel clock or data throughput: you have a pipe and the amount of information which can flow in the pipe depends on the pipe size, not how you rearrange the data afterwards (row x columns of an image). Pixel clock depends on the resolution, refresh rate and timings for the monitor.
It's not convenient to list all the exotic resolutions that a panel manufacturer might wish to do, so instead, you have the most common ones listed.
The amount of pixels is
2650x1440 = 3.816 Mpixels
2560x1080 = 2.765 Mpixels
There is so much difference that the timing won't make a big difference in working/not working.
But you seem to refer to the HDMI max resolution of a particular DisplayLink IC series.
I would advise you use DisplayPort so you can get a higher refresh rate in all conditions if you use that series. Alternatively, you can use a product with the latest DisplayLink chip which can drive 4Kp60 on any output type (which standard supports it, of course)
http://support.displaylink.com/knowl...rticles/525038
Kind regards,
Alban