Upgrading motherboard and video card on an HP Desktop Computer?

lolzmao Asked: Upgrading motherboard and video card on an HP Desktop Computer?

So, the name of the desktop computer is HP Pavilion a6453d. My budget for the total upgrade is $350. I was wondering if some of you guys could give me tips on what specific video card and/or motherboard should I buy if I would like to make it a gaming computer (runs games at med-high settings). Changing CPU and Power Supply is not an option(unless its urgently needed). Please take note that the parts will be only bought in the Philippines.

Specifications:
HP Pavilion a6453d Desktop PC Product Specifications
Product release information
Product number
KN293AA
Release date
19-Feb-2008
Country/region sold in
Philippines
Motherboard
MS-7525 (Boston)
Manufacturer: MSI
Form factor: microATX – 24.4 cm (9.6 inches) x 24.4 cm (9.6 inches)
Chipset:
Northbridge chipset: Intel G31 Express
Southbridge chipset: Intel ICH7
Memory sockets: 2 x DDR2
Front side bus speeds: 1333/1066/800 MHz
Processor socket: 775
Expansion Slots:
1 PCI Express x16 slot for graphics card
2 PCI Express x1 slots
1 PCI slot

Processor
Intel Core 2 Duo E2160
Operating speed: Up to 1.8 GHz
Number of cores: 2
Socket: 775
Bus speed: 800 MHz
Processor upgrade information
Socket type: 775
Motherboard supports the following processor upgrades:
Core 2 Duo E7xxx (Wolfdale-M)
Core 2 Duo E4x00 (Conroe)
Pentium E2xxx series (Conroe)
Celeron Dual Core E1xx0 series (Conroe)
Celeron 4xx series (Conroe)
Memory
1 GB
Amount: 1 GB
Speed: PC2-6400 MB/sec
Memory upgrade information
Dual channel memory architecture
Two 240-pin DDR2 DIMM sockets
Supported DIMM types:
PC2-5300 (667 MHz)
PC2-6400 (800 MHz)
Non-ECC memory only, unbuffered
Supports 2GB DDR2 DIMMs
Supports up to 4 GB* on 32 bit PCs
32 bit PCs cannot address a full 4.0 GB of memory.
Video graphics
Integrated graphics using Intel GMA 3100
*Integrated video is not available if a graphics card is installed.
Integrated graphics using Intel GMA 3100
Also supports PCI Express x16 graphics cards
Sound/Audio
Integrated Realtek ALC662 Audio
*Integrated video is not available if a graphics card is installed.
Audio CODEC: Realtek ALC662
5.1 channel high-definition audio
Networking
LAN: 10-Base-T
Interface: Integrated into motherboard
Technology: Realtek 8101E
Data transfer speeds: up to 10/100Mb/s
Transmission standards:10-Base-T Ethernet

Modem: 56K WinModem
Interface: PCI 2.2
Data transfer speeds: up to 56 kbps for V.92 connections*
Transmission standards: V.92, V.90, V.44, V.34*
* Features must supported by the ISP at time of connection.
Hard drive
160 GB
Figure 4: Hard drive
Image of hard drive
Size: 160 GB
Interface: SATA
Transfer rating: 3.0 Gb/sec
Rotational Speed: 7200 RPM

CD/DVD disc drive
SuperMulti 16X DVD(+/-)R/RW 12X RAM (+/-)R DL LightScribe SATA drive
Interface: SATA
Data buffer memory: 2 MB
Maximum storage capacity: 8.5 GB
Must use Double-Layer media discs in order to take advantage of the DL technology
Must use LightScribe-enabled media discs and supporting software in order to take advantage of the LightScribe technology

Power Supply
250W
250W power supply
I/O Ports
Front I/O ports
USB: 2
Headphone: 1
Microphone: 1