First of all, a lga 2011 based build is overkill for gaming. Also, Metro 2033 isn't necessarily graphically intense, just poorly optimized. Even the gtx 670 struggles to run it on ultra settings. For RAM, all you need is a 2x4gb kit of RAM rated at 1600MHz with 9-9-9-24 cas latency.
In order to make things easy, copy and paste the following template into your post and edit the examples to suit your needs:
Approximate Purchase Date: e.g.: this week (the closer the better)
Budget Range: (e.g.: 300-400) Before / After Rebates; Before / After Shipping
System Usage from Most to Least Important: (e.g.: Folding@Home, gaming, surfing the internet, watching movies)
Are you buying a monitor: Yes / No
Parts to Upgrade: (e.g.: CPU, mobo, RAM) **Include Power Supply Make & Model If Re-using**
Do you need to buy OS: Yes / No
Please note that if you're using an OEM license of Windows, you will need a new one when buying a new motherboard.
Preferred Website(s) for Parts: (e.g.: newegg.com, ncix.com -- to show us selection & pricing)
Location: City, State/Region, Country - we need to know where these parts are being assembled and whether there are good store-only deals available
Parts Preferences: by brand or type (e.g.: I would like to upgrade to Intel CPU)
Overclocking: Yes / No / Maybe
SLI or Crossfire: Yes / No / Maybe
Your Monitor Resolution: (e.g.: 1024x768, 1280x1024, 1440x900, 1600x1200, 1680x1050, 1920x1080, 1920x1200 or if you're upgrading please state what you'd want to get)
Additional Comments: (e.g.: Need to have a window and lots of bling, I would like a quiet PC. Please also list specific software or games you're using)
And Most Importantly, Why Are You Upgrading: (e.g. I'm having trouble running game X or my PSU broke)