VRAM usage/graphics card recommendations - 2 monitor setup

H I folks,

Looking for some advice here...

I will shortly have this setup once my new GTX 970 arrives.

• Dedicated Flightsim PC: GTX 970 4Gb
• General Purpose (GP)  PC: HD 4770 512MB
• Shared Monitor via DVI KVM: Samsung 24", 1080p

I am looking to potentially upgrade the 24" monitor I have with a 1440p monitor replacement. I am not convinced a 4K monitor is worthwhile.

So the question is, if I move to 1440p for my Flightsim PC, I am reasonably confident the GTX 970 can handle the workload,  but I was wondering if the HD 4770-equipped PC for general purpose/office apps is going to cut the mustard with the small 512Mb of VRAM it has, if I want to use all the real estate the new 1440p monitor provides?

I doubt it.

It would seem to me a reasonable approach would be to upgrade the "GP PC" graphics card with a 2Gb card.

Would this make sense?

I came across this review...

http://www.tweaktown.com/tweakipedia/89/much-vram-need-1080p-1440p-4k/index.html

What would you recommend?

Thx

PS. Just realized an error in the title. Should read "2 PC setup", not "2 Monitor setup!"