Can't decide if I need to upgrade my PC or not?

I made a mistake a while back and bought a pre built computer. Here's a link to it on amazon. "http://www.amazon.com/Lenovo-X315-Gamin… Make sure you look at the a8 version. I was new to PC gaming and thought it was a good deal, but I ended up not being able to play most the games I had bought so I replaced the graphics card with a 2gb gtx 960 and the power supply with a 600w. And I'm still not getting the type of performance I want to be. I feel like it should be better. I see my fps drop down to 20 in games like fallout 4 and just cause 3. So I thought huh maybe my cpu is the problem so I looked at the i5 4690k and the i7 4790k and I didn't see a huge difference in performance I mean not $100 worth at least. And I couldn't find a video comparing my cpu the a8 7600 and the i5 4690k so I looked it up on cpu boss and my cpu I have now had a higher score. So my question is what do I need to upgrade. As far as I can tell I would think I should be getting around 40fps on medium setting in most games at least. I think I could be happy with 40fps for now. Any ideas would help.

My guess is the motherboard they used is garbage. Any decent gaming rig starts with a solid motherboard.

Start there. I couldn't find which MB they used, so pop it open and find out what it is. Start your research there.

Okay, look. Intel CPUs are, and always will be, VASTLY more powerful amd CPUs. To upgrade to an intel series CPU, you would also need to buy a motherboard with the right socket for it. And you should have got the 4gb 960. I can play all the games you have listed with that lol. But the problem most likely lies in your cpu, as it's really not the greatest. If you do have the money for it, buy a new motherboard and a good i5. The difference between the newer i5s and i7s really isn't worth the money in desktops.

Th guy telling you intel is vastly superior is full of ****. My powersupply took out my FX 8350 build so I went back with an i5 4690k, the damn thing maxes out all the cores and textures quit loading. Never had that problem with the 8350 and the damn i5 won't even run a small overclock stable.

Your link to your computer model doesn't lead anywhere, it's a broken link, you might want to put that link up properly this time.

Anyways, the CPUBoss site is a bit misleading. The score it comes out with is a comparison of not just the CPU, but also the embedded graphics capabilities of that processor. So the AMD integer units are a bit underwhelming compared to the Intel ones, but the AMD graphics units are the exact opposite and overwhelms the Intel graphics. However, you've got an Nvidia GTX 960 video card, so you're not using the embedded AMD graphics at all, so the AMD graphics comparison is completely useless to you. This makes AMD APU's look more powerful than they actually are, and on the opposite end, it makes AMD's 6 & 8-core FX CPU's (without embedded graphics) look less powerful than they actually are. I'd suggest using the Passmark website instead to do a straight CPU-to-CPU comparison, rather than an APU-to-APU comparison.

PassMark Software - CPU Benchmark Charts
http://www.cpubenchmark.net/.../index.php

As for what you need to upgrade? Probably nothing, you just need to use your existing hardware more efficiently. To that end, then I would suggest that you run the Nvidia GeForce Experience program (it should be included with your GTX 960). That program can re-optimize all of the settings in your games and set them to the maximum performance capabilities of your GPU. I have a GTX 750 Ti, myself, and when I ran Geforce Experience on my games, it was a huge difference in performance that I got back. In many cases, I had some settings turned up too high, Experience turned them down a little bit, not all of the way down to low, but somewhere in the middle, and the new settings were great, I didn't even notice the difference in quality, and in fact the additional frame rates made them look better!