CyberPowerPC - Unleash The Power

I purchased a cyberpower pc a few months back now,I was receiving lag in games which in theory I should of been able to play,I decided to upgrade the gpu from a power colour 6850 to a sapphire 7870. I'm still getting the same problems,it seems to be in certain games,for instance i can play bf3 with ultra textures and maintain 60fps yet I try to play skyrim or amnesia and i get less fps than bf3? :/ I will post my specs below,please note the psu was upgraded to a 850w I'd appreciate your help.

Ultra Scylla SE (NO MONITOR)
ULTRA_SCYLLASEZ, http://www.cyberpowersystem.co.uk/system/Ultra_SCYLLA_SE/
*BASE_PRICE: [+571]
BLUETOOTH: None
CABLE: None
CAS: CoolerMaster HAF 912 Mid-Tower Gaming Case w/ Adjustable HDD Cage (Black Color)
CASUPGRADE: NONE
CD: 24X Double Layer Dual Format DVD±R/±RW + CD-R/RW DRIVE. (BLACK COLOR)
CD2: NONE
COOL: NONE
CPU: AMD FX-6100 3.30 GHz Six-Core AM3+ CPU 6MB L2 Cache & Turbo Core Technology
CS_FAN: Default Case Fan
DONGLES: NONE
EXPAN: NONE
FA_HDD: None
FAN: Asetek 510LC / Xtremegear Liquid Cooling system w/ 120mm Radiator (Asetek CPU Water Cooling ***Overclockable XXX***)
FLASHMEDIA: None
FLOPPY: NONE
FREEBIE_CS: None
FREEBIE_NVVC: None
FREEBIE_OS: None
GLASS3D: NONE
HDD: 1TB SATA-II 3.0Gb/s 16M Cache Hard Drive (Single Hard Drive)
HDD2: NONE
HOMEINSTALL: NONE
IEEE_CARD: NONE
KEYBOARD: NONE
MEMORY: 8GB (4x2GB) PC10666 DDR3/1333mhz Dual Channel Memory (Corsair Value Select or Major Brand)
MODEM: NONE
MONITOR: NONE
MONITOR2: NONE
MONITOR3: NONE
MOTHERBOARD: ASUS M5A78L-M/USB3 AMD 760G (780L) Chipset DDR3 Socket AM3+ Micro-ATX w/ 7.1 Audio, GbLAN, USB3.0, SATA-III, 1 PCIe X16, 1 PCIe X1, & 2 PCI
MOUSE: NONE
NETWORK: ONBOARD 10/1000 NETWORK CARD
OS: Microsoft® Windows® 7 Home Premium (64-bit Edition)
OVERCLOCK: No Overclocking
POWERSUPPLY: 700 Watts Power Supplies (Cyberpower 700watt Gaming Power Supply (No Overclocking recommended))
RUSH: NONE
SOUND: HIGH DEFINITION ON-BOARD 7.1 AUDIO
SPEAKERS: NONE
TEMP: NONE
UPS: None
USB: Built-in USB 2.0 Ports
USBHD: NONE
VIDEO: AMD Radeon HD 6850 1GB GDDR5 16X PCIe Video Card , Eyefinity 3 capable (Major Brand Powered by AMD)
VIDEO2: None, or On-Board Integrated Graphics
WAP: NONE
WARRANTY: STANDARD WARRANTY: 3 Year Labour, 1 Year Parts, 1 Month Collect and Return plus Life-Time Technical Support
WNC: NONE
XWNA: NONE
_PRICE: (+571)
_view_: d

That's what bothers me,I should be able to play these games with no problem yet my system seems to be struggling,how do I go about changing the voltage? also are there any specific case fans you could recommend to maximise the airflow? thanks.

Still no improvement after the voltage change,Will install some case fans see if that fixes the problem. Is there any chance it's the hdd? on the windows experience it gets a rating of 5.9 whilst pretty much everything else is a 7.9.

5.9 is standard for an HDD. You need a fast SATA III SSD to get 7.9.

Does this rule out the overheating VRMs then? Wish I could just find the solution to the problem :/

downloaded all the application profiles still no change,thanks for your help,hopefully find a solution soon.

http://3dmark.com/3dm11/3208923;jsessionid=pp7cwdz111rv240jd8ok5uj8

I've noticed on there that my gpu ain't showing the correct clocks,In catalyst centre its down as 1000mhz and 1200mhz unless its in idle.
Also is it just a coincidence its just the games through steam that I'm finding problems with?
BF3 is set to auto settings yes.

Amnesia settings

BF3 settings

I tried using task manager to close steam,It does seem to speed up but it still seems like I'm loosing fps somewhere.

Yes,But it is noticeable without fraps to monitor the fps the game stutters. I went to the extreme of a fresh install of steam as it used to be fine,So far it seems to have fixed the issue's in amnesia,but this is just at a 5 min glance. Any Idea's how steam could affect the performance if it was steam that was causing issue's?

Problem seems to be solved now,Looks like a bad driver,I reinstalled my gpu drivers and everything is fine now, consistent fps. Thanks for all your help.