How will switching to a 2560x1440 monitor affect my X220?

[Sleepless]

Hello experts!
My X220 is connected to an external 1920x1080 (24") monitor. The X220 runs Windows 10 on i7-2640M @ 2.80GHz, 4GB Ram, 1GB SSD. The GPU is an Intel HD 3000.
I mostly use the laptop for programming, word processing, browsing etc, but I watch the occasional YouTube/Netflix movie. No gaming!
I am thinking of getting a new 2560X1440 (27") monitor.
How would that affect performance? Will I be able to watch videos? Will my CPU become much hotter?
Any experience/knowledge that you have will be highly appreciated!
Thank you!

[RealBlackStuff]

X220 Maximum external resolution:
2560x1600 (DisplayPort)@60Hz;
2048x1536 (VGA)@75Hz;
1920x1200@60Hz (single-link DVI-D via cable 45J7915)

[Sleepless]

X220 Maximum external resolution:
2560x1600 (DisplayPort)@60Hz;
2048x1536 (VGA)@75Hz;
1920x1200@60Hz (single-link DVI-D via cable 45J7915)

Thank you! The specs say that the maximum external resolution is 2560x1600, so I assume 2560x1440 should also work? Or am I missing something here?

I was more concerned about the performance, since the new monitor will have 1.8x times the number of pixels, so I am assuming that the CPU and/or GPU need to work almost 2x as hard? How will that affect ability to watch videos? CPU heat? Thank you!

[RealBlackStuff]

As long as you don't jack up the refresh rate, you should be fine.
I would recommend though to also get more RAM (go to 8gb, even 16GB is possible).