Intel i5-3350P CPU what GPU should I buy?

If you do upgrade your CPU, what would it be? As it stands the GTX1050Ti looks like a better candidate but we;re also going to need to know the make and model of your PSU(as well as it's age) and ofc the rest of your system's specs.

Screen resolution matters as well, the higher it is the more power you need to run games at high settings.
For 1080P a 1060 is a pretty good option and the 1050Ti mentioned should also be good enough. For lower res you could get away with somehting even cheaper.

Getting the PSU and Graphics card now will not cause problems, in fact you may find you don't need that CPU upgrade after all depending on what games you play. The i5 is good enough for most games already I would expect. Just be sure it's a good quality PSU.

Missed that, the best you can do with 1155 is an i7 3770 or 3770K. If you want to go 7700K you are looking at a new motherboard based on the Z270 chipset most likely and they are not especially cheap. There are a lot of options, and AMDs new Ryzen CPU's are worth considering too. Something like an R7 1600X, 1700 or 1700X might be worth pricing up as an alternative.

This will be longer than many replies, please read it all. I could have written more, however, you should at the least consider and be aware of the following. Please be aware that I did not proof read this, so there may be some spelling or grammar errors.

If your primary purpose is gaming then you do not need an i7 7700K.

You would be better off getting a GTX 1070 and a lesser CPU to keep cost equal, if money is a concern. For gaming an i7 7600K is a very viable CPU and can easily be overclocked using a good air cooler, such as the Noctua NH-U14S. If your case is not large enough for that CPU cooler the Noctua NH-U12S is very good, although physically smaller.

Depending upon what games you like to play it is possible that your current CPU will work fine with a better GPU. Get a GTX 1070, it will still outperform at GTX 1060 with your current CPU. The reason you should not get the GTX 1060 is because it can drop more frames than a 1070. You will get more frames per second and more importantly better 1% low and .1% low, which are more important than average FPS because they are a more accurate indication if your game will stutter or be jerky.

One thing you might need to do is go to your motherboard web site and upgrade your BIOS because some motherboards do not support GTX 900 and 1000 series graphics cards with an old BIOS. First, install the new video card, if it works there is no need to upgrade your BIOS. It is little things like this that most people do not know and they believe they received a defective video card if it does not work.

Your next purchase after a video card may need to be a power supply. You did not mention what you have. If you eventually get an i7 7700K I suggest at least a good 650 watt power supply, for best performance a good quality power supply is needed and 50% load provides the best power draw from the wall [lower electric bill each month]. One of the following power supplies will work. If you purchase a Corsair DO NOT get a CX series, they are low quality. It is very important to have a high quality power supply - and it is usually one of the items that people skimp on because they do not know the many problems caused by purchasing a low quality power supply [in an effort to save money].

Here are some from Newegg, however, you can purchase them someplace else if the price is lower. For a review of a power supply you are thinking about getting JonnyGURU does an outstanding job http://www.jonnyguru.com/index.php
Newegg:

https://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=power+supply&ignorear=0&N=100006656%2050001459%2050001697%204814%20100007657%20600014087%20600014085%20600037998%20600112163&isNodeId=1