i have the same situation
main is P2414H IPS 60hz but now i have a gtx980ti and i want to play better with 144hz or 120hz or somethning, i don't know....
If you are just planning on stepping up to 144hz and stay at 1080p, then I would say its not worth it. Even more so because you have an IPS panel right now, and 6ms IPS is very decent IPS. There really aren't much faster versions of IPS (they may say so on the box, but IPS pixel response is simply limited, best panels get 6/8-10ms G2G and that is being optimistic, they use overdrive to get there in many cases, which can produce side effects).
Consider your gameplay. Are you competitive, look at fast TN or high refresh IPS. Do you like gazing at in-game vistas and are you a sucker for eye candy, consider IPS/VA at higher resolutions @ 60-75hz. Do you really want to maintain high FPS and motion resolution, but don't play much competitively, look at 1080p or 1440p/120hz or better IPS/VA.
I belong to that last category, and I bought an Eizo FG2421, no regrets. If you are looking into high refresh 1080p VA and highest possible static contrast/deep blacks, this is the one. And even this panel isn't perfect; it has a warm up time in which dark/light transitions 'smear' a bit which is visible if you look for it, and it has a very slight tone shift off-center. However it has an unmatched strobing functionality (much better than Lightboost) and very deep blacks.
My personal checklist of must-haves when buying gaming monitors right now is this, may also help you:
- backlight uniformity must be above average / good, little to no backlight bleeding or IPS glow (this is where cheap IPS has issues, and this is a quirk you cannot get past. IPS glow will show in dimly lit rooms and it is super annoying, I'd say more so than a good TN's contrast shift)
- must have strobing backlight (one of the things 'you can't get back from' once you know what it is, basically it gives you the fluid CRT monitor feel back and eliminates blur)
- must have decent static contrast, at the very least 1000:1 (dynamic contrast = shit) Most modern IPS has 1000:1 and it ends there. If you want better, you need VA.
- native(!) 8 bit (+FRC optional) panel with good sRGB coverage
- preferably at least 75hz (if 100+hz panels are out of reach)
Hope this helps, because I really don't want to choose for you. Take your time in choice of monitor, because these things can last you many builds. Also don't let marketing decide for you, keep it to technical, hardware specific arguments and stay clear of falling for the '80 gazillion to 1 contrast ratio' bullshit. Also think hard on Gsync, if you get high refresh panels, because in most cases its not required and it is a bit of a vendor lock in.
If you want really solid reviews on monitors, check
www.tftcentral.co.uk