PC upgrades for gaming

Hello. I want a PC that can run MMO's like WOW and Rift at max settings with really high frame rates and responsiveness during raids and in high player pop. areas. My current computer specs are:

OS Name Microsoft Windows 7 Home Premium
Version 6.1.7601 Service Pack 1 Build 7601
OS Manufacturer Microsoft Corporation
System Manufacturer Gateway
System Model FX6840
System Type x64-based PC
Processor Intel(R) Core(TM) i7 CPU 870 @ 2.93GHz, 2934 Mhz, 4 Core(s), 8 Logical Processor(s)
BIOS Version/Date American Megatrends Inc. P01-A3, 5/17/2010
SMBIOS Version 2.6
Windows Directory C:\Windows
System Directory C:\Windows\system32
Boot Device \Device\HarddiskVolume2
Hardware Abstraction Layer Version = "6.1.7601.17514"
Installed Physical Memory (RAM) 8.00 GB
Total Physical Memory 7.99 GB
Available Physical Memory 4.97 GB
Total Virtual Memory 16.0 GB
Available Virtual Memory 12.7 GB
Page File Space 7.99 GB
ATI Radeon HD 5700 Series graphics card

This current system works OK but is far from optimal. My question to you guys is- Do I just need a couple upgrades or do you think I should just get a new system? I don't know a whole lot about computers, so anything you guys can help direct me with would really help. Thanks!!
 
Looking at your system specs I would say your cpu is fine and you have 8 gigs of RAM that is also quite fine. In your case I would say you need to upgrade your Graphics card. Can you tell us the make and model of your motherboard as well as make, model, and amount of wattage of your power supply? In addition size, make and model of your hard drive and how much space you have on it that is free.
 
Back