Gateway DX4860 GPU Upgrade

Hello Everyone.
 
I want to Upgrade my Gateway DX4860's GPU. I haven't done anything like this so please bare with me. It comes with an Intel Graphic Family, which isn't enough. I would be playing games like Batman Arkham City and forth coming NFS Most Wanted 2. The budget is of ~100$. I hope that's enough to get a GOOD graphics card.
 
Thanks 
 
PS - Here's the specs - 
 
  • Manufacturer:Gateway
  • Part Number:PTGCPP2017

General

  • Desktop typeBudget desktop system
  • Packaged Quantity1
  • Product Form FactorTower
  • Built-in DevicesKeyboard,
    LED panel

Processor / Chipset

  • Type2nd Gen Core i5,
    Intel 2 i5-2320 / 3 GHz
  • Number of CoresQuad-Core
  • 64-bit ComputingYes
  • CPU Qty1
  • Max CPU Qty1
  • Chipset TypeIntel H67 Express

Cache Memory

  • Installed SizeL3 cache - 6 MB
  • Cache Per Processor6 MB

RAM

  • Installed Size6 GB / 16 GB (max)
  • TechnologyDDR3 SDRAM
  • Memory Speed1333 MHz
  • Memory Specification CompliancePC3-10600
  • Form FactorDIMM 240-pin

Hard Drive

  • TypeStandard
  • Capacity1 x 2 TB
  • Interface TypeSerial ATA-300
  • Spindle Speed5400 rpm

Storage Controller

  • Type1 x Serial ATA - Integrated
  • Controller Interface TypeSerial ATA-300

Hard Drive (2nd)

  • TypeNone

Hard Drive (3rd)

  • TypeNone

Optical Storage

  • TypeDVD±RW / DVD-RAM

Floppy Drive

  • TypeNone

Optical Storage (2nd)

  • TypeNone

Card Reader

  • TypeCard reader

Storage Removable

  • TypeNone

Monitor

  • Monitor Typenone.

Graphics Controller

  • Graphics Processor / VendorIntel HD Graphics 2000 Dynamic Video Memory Technology 5.0

Input Device

  • TypeMouse,
    Keyboard

Audio Output

  • TypeIntegrated

Telecom

  • ModemNone

Networking

  • TypeIntegrated
  • Wireless LAN SupportedYes
  • Data Link ProtocolFast Ethernet,
    Ethernet,
    Gigabit Ethernet,
    IEEE 802.11b,
    IEEE 802.11n,
    IEEE 802.11g
  • Compliant StandardsIEEE 802.11g,
    IEEE 802.11n,
    IEEE 802.11b

Printer

  • TypeNone

Miscellaneous

  • Features802.11b/g/n Wireless LAN

Expansion / Connectivity

  • Slots1 (total) / 0 (free) x Processor,
    4 Memory - DIMM 240-pin
  • Interfaces1 x Display / video - VGA - 15 pin HD D-Sub (HD-15),
    1 x Audio / video - HDMI - 19 pin HDMI Type A,
    10 x Hi-Speed USB - 4 pin USB Type A,
    1 x Network - Ethernet 10Base-T/100Base-TX/1000Base-T - RJ-45,
    Audio - Line-in,
    Audio - Line-out

Power

  • Device TypePower supply
  • Power Provided300 Watt

Operating System / Software

  • OS ProvidedMicrosoft Windows 7 Home Premium 64-bit Edition
  • Microsoft Office PreloadedIncludes a pre-loaded image of select Microsoft Office 2010 suites. Purchase an Office 2010 Product Key Card or disc to activate preloaded software on this PC.
  • SoftwareBing Toolbar,
    Microsoft Office 2010 Starter,
    Windows Live Essentials

Manufacturer Warranty

  • Service & Support1 year warranty
  • Service & Support DetailsLimited warranty - Parts and labor - 1 year,
    Technical support - Phone consulting - 1 year

Dimensions & Weight

  • Width7.1 in
  • Depth15.8 in
  • Height12.6 in

I would like to upgrade my Gateway DX4860's GPU. The stock one is an Intel Graphics Family. I would be playing Batman : Arkham City and forth coming NFS Most wanted.

My budget is~100$. Any suggestions?

Here's the specs -

 

  • Manufacturer:Gateway
  • Part Number:PTGCPP2017

General

  • Desktop typeBudget desktop system
  • Packaged Quantity1
  • Product Form FactorTower
  • Built-in DevicesKeyboard,
    LED panel

Processor / Chipset

  • Type2nd Gen Core i5,
    Intel 2 i5-2320 / 3 GHz
  • Number of CoresQuad-Core
  • 64-bit ComputingYes
  • CPU Qty1
  • Max CPU Qty1
  • Chipset TypeIntel H67 Express

Cache Memory

  • Installed SizeL3 cache - 6 MB
  • Cache Per Processor6 MB

RAM

  • Installed Size6 GB / 16 GB (max)
  • TechnologyDDR3 SDRAM
  • Memory Speed1333 MHz
  • Memory Specification CompliancePC3-10600
  • Form FactorDIMM 240-pin

Hard Drive

  • TypeStandard
  • Capacity1 x 2 TB
  • Interface TypeSerial ATA-300
  • Spindle Speed5400 rpm

Storage Controller

  • Type1 x Serial ATA - Integrated
  • Controller Interface TypeSerial ATA-300

Hard Drive (2nd)

  • TypeNone

Hard Drive (3rd)

  • TypeNone

Optical Storage

  • TypeDVD±RW / DVD-RAM

Floppy Drive

  • TypeNone

Optical Storage (2nd)

  • TypeNone

Card Reader

  • TypeCard reader

Storage Removable

  • TypeNone

Monitor

  • Monitor Typenone.

Graphics Controller

  • Graphics Processor / VendorIntel HD Graphics 2000 Dynamic Video Memory Technology 5.0

Input Device

  • TypeMouse,
    Keyboard

Audio Output

  • TypeIntegrated

Telecom

  • ModemNone

Networking

  • TypeIntegrated
  • Wireless LAN SupportedYes
  • Data Link ProtocolFast Ethernet,
    Ethernet,
    Gigabit Ethernet,
    IEEE 802.11b,
    IEEE 802.11n,
    IEEE 802.11g
  • Compliant StandardsIEEE 802.11g,
    IEEE 802.11n,
    IEEE 802.11b

Printer

  • TypeNone

Miscellaneous

  • Features802.11b/g/n Wireless LAN

Expansion / Connectivity

  • Slots1 (total) / 0 (free) x Processor,
    4 Memory - DIMM 240-pin
  • Interfaces1 x Display / video - VGA - 15 pin HD D-Sub (HD-15),
    1 x Audio / video - HDMI - 19 pin HDMI Type A,
    10 x Hi-Speed USB - 4 pin USB Type A,
    1 x Network - Ethernet 10Base-T/100Base-TX/1000Base-T - RJ-45,
    Audio - Line-in,
    Audio - Line-out

Power

  • Device TypePower supply
  • Power Provided300 Watt

Operating System / Software

  • OS ProvidedMicrosoft Windows 7 Home Premium 64-bit Edition
  • Microsoft Office PreloadedIncludes a pre-loaded image of select Microsoft Office 2010 suites. Purchase an Office 2010 Product Key Card or disc to activate preloaded software on this PC.
  • SoftwareBing Toolbar,
    Microsoft Office 2010 Starter,
    Windows Live Essentials

Manufacturer Warranty

  • Service & Support1 year warranty
  • Service & Support DetailsLimited warranty - Parts and labor - 1 year,
    Technical support - Phone consulting - 1 year

Dimensions & Weight

  • Width7.1 in
  • Depth15.8 in
  • Height12.6 in

hd 7770 will be fine for you with stock psu anything more and you will need a psu upgrade

http://www.newegg.com/Product/Product.aspx?Item=N82E16814125444

uses 64w, as good as the 7770