I have built a pc and am happy, but how good is it and where should I upgrade?

My Build:
case: some old 2003 windows xp case (with only 3 fans it runs cold anyway)
Board: Msi z77a-G43 L1155 chipset
Processor: Intel pentium G2120 3.1 GHZ
Power supply: coolermaster 500W
Graphics card: EVGA Nvidia Geforce GTX 650 1GB
HDD: 1x HGST 500GB(OP system) 1x HGST 1TB(games etc.)
Ram: 2x Corsair Vengance 8gb (1600MHz) both in either the blue or black slots (refer to pic of board)

First off Im a noob. All of the slots other than sata 2/3, usb 2/3, processor, and Graphics card slots confuse me. I kind of went with the flow building this and it cost way more than it should've and I know for gaming I don't need 16GB of ram although it is nice for using Autodesk Inventor (3d cad program).

Like I said in the title I am happy with this build but I have been finding that I max out my CPU a lot and am considering an i3 with the L1155 chipset <---(is this the right term?) but I have recently come to the conclusion that, that socket type is outdated technology. How should I go about upgrading, CPU and others later or board and CPU at once and get a newer socket type? Any advice is very appreciated, Thankyou in advance.

,Brad

pcpartpicker.com

Look into cpus on your socket.

Large upgrade/new pc
Wait for 300 AMD series, or get 900 series Nvidia.

Pic of case?


Pardon the bad cable management and I actually have 4 fans, but the PSU only gets a little warm during decent gaming sessions, but only enough to slightly warm my feet on a cold day when it was on the floor.

Holy cow I didn't realize that you could get and i3 3240 for $80 on ebay (they have the money back guarantee so no risk), I think I will do that thanks for steering me into the right direction

running auto desk you need moor cors on your cpu. my son attends rose Holman. for a desktop we used a amd fx prosecer and a gtx 560 ti an fx 8350 will bring inventor to life' and adding an ssd to the build will bring down your stress level when booting up.

The first time I read this I thought it was spam. Now I know that it's just bad punctuation..