Help with first gaming PC

Alright guys so this is my first PC build I'm trying to shift from Console gaming over to PC but I'm not really sure where to go from here. I have a budget limit of 400-450$ since that's what I was going to pay for a ps4

I should also mention I want to do some light modding as well 

What kind of games do you plan on playing? And do you have any spare parts that you can use for this build such as a monitor, mouse, keyboard, HDD, etc.? Anything to help free up the budget at all would be awesome.

Do peripherals need to be included in the budget? (mouse, keyboard, headset, monitor)

Here's a little something I threw together: http://pcpartpicker.com/p/bGssxr

I'm not overly fond of the dual core, but it was the only way I could squeeze in the R9 280. At $450, your options are extremely limited. If you really want a gaming PC, I recommend you save up another hundred or two. That will open up a lot more options.

And here's a build based around an AMD quad core: http://pcpartpicker.com/p/q72Tqs

Now, after reading that bit of information, I know what's going to go through your mind: "the PS4 is cheaper and appears to be a better option." If you factor in the cost of games for the PS4 vs the PC, that statement immediately becomes false. Games on PC are far cheaper compared to console. Not to mention, your selection of games increases dramatically with Steam. Also, if you go with the PS4, that light modding you were planning on doing becomes virtually impossible. Consoles are extremely locked-down and offer very little wiggle room as far as modding is concerned.

I could probably go up to 500$ and I mostly play Girls person shooters, elder scrolls, and civilization. 

Well, it really depends on how much you want to spend in the end and wether you want to do those stupid mail-in rebates. A beefy GPU is key for your experience, so I went with the R9 280 in my build suggestion. You could downgrade that to a 270 or take a look at the 750Ti if you want to save some more.

http://pcpartpicker.com/p/2KgKdC

Like deus Ares said, the FM2+ road is probably the way to go and just like him I'm hesitant to recommending those Intel dual-cores.

If you want to check out more builds or verify if ours make any sense, go to http://www.logicalincrements.com/

If you are willing to try Gaming on Linux you can cut the cost of Windows out completely and get some great games of all genres on Linux through Steam and elsewhere. Civ 5 is on Linux FYI.

I dont know if you realized it or not but you put 1333 Mhz RAM in this system. Not good for AMD.

I'm using the parametric filter, so it automatically selects the cheapest 2x4GB kit every time you reload the page. Why is 1333 MHz RAM not good for AMD?

I decided to go 500$ I got this build not sure what do you guys think abiut it http://www.amazon.com/gp/aw/c/ref=psd_msi_n_B0088PUEPK_B00P9H3IHG

That link doesn't work for me.