CPU aside, that's a pretty low-end GPU in terms of modern gaming.
However, you need to be thinking carefully about how you setup VSYNC:
1) VSYNC OFF
2) VSYNC ON
3) Adaptive VSYNC
4) Adaptive "HALF" VSYNC
With VSYNC OFF, your GPU spits out new frames as fast as possible. So you don't have to hit 144FPS. The con is that you get screen tearing.
With VSYNC ON, you need to be able to output a solid 144FPS or else you get stuttering. Maintaining 144FPS (at 1920x1080) is impossible, except for the basic desktop and very light games.
Adaptive VSYNC:
This just toggles VSYNC ON or OFF. If you drop below the target you get SCREEN TEAR instead of stuttering which is usually the better trade-off. I generally aim for no more than 10% of the time below the target.
Adaptive "HALF" VSYNC:
Same as above, but you are capping at 72FPS on a 144Hz monitor. It's going to be a good choice for some of the games you play.
Other:
You're going to have to decide on the above as well as whether the tradeoff of low quality is worth the FPS difference. Obviously you are on a budget (and haven't said what CPU etc you have) but maybe that will help a bit.
*Using VSYNC OFF is often the best choice for a game like CSGO. If you can output high enough FPS the screen tear is barely noticeable. What you may find ODD is that in some cases apparently 60Hz monitors have less screen tear than 144Hz, with VSYNC OFF, and at the same FPS.
The amount of screen tear has a few factors, and a big one is the ratio of FPS to refresh rate. You really have to experiment.
(and 1600x900 may be a better choice as well if trying to keep FPS high with only a GTX750)