ATI Radeon 9000 as very low-end HTPC

I want to use this card http://www.microcenter.com/single_product_results.phtml... with a 300 watt power supply, the reason I'm stuck with this sucky deal is I'm getting it in two days and no PCIe slot on computer. I need this with its DVI cable support, question is will it work? Exact computer is a HP Pavilion a744x that has not been upgraded.

SPECS of comp

Hardware
Base processor
Pentium 4 515 2.93 GHz

*
533 MHz Front side bus
*
Socket LGA775

Chipset
Intel 915G
Motherboard

*
Manufacturer: Asus
*
Motherboard Name: PTGD1-LA
*
HP motherboard name: Goldfish-GL8E

Memory
Component Attributes
Memory Installed 512 MB (2 x 256)
Maximum allowed 4 GB (4 x 1GB) requires the replacement of the installed 256 MB DIMMs
Speed supported PC3200 MB/sec
Type 184 pin, DDR SDRAM
DIMM slots Four
Open DIMM slots Two
Hard drive

*
120 GB SATA
*
7200 rpm

DVD+R/+RW (8X) DL
(must use Double-Layer media discs in order to take advantage of the DL technology)
type Attributes
DVD+R Write Once 8X
DVD+RW Rewritable 4X
DVD ROM Read 12X
CD-R Write Once 24X
CD-RW Rewritable 40X
CD-ROM Read 40X
Form Factor 5.25 inches
Storage Capacity 8.5GB
DVD-ROM drive
Maximum speed: 16x
Modem
PCI K56flex data/fax modem
Video graphics
Integrated, no AGP slot
Sound/audio
Integrated High Definition audio

* Realtek ALC 880 chipset
* 8-channels for Full Dolby 5.1/6.1/7.1 surround sound support with Dolby Pro Logic IIx

Network (LAN)
Integrated 10/100Base-T networking interface
Power Supply

*
AC input voltage (47-63Hz):
o 100-127V/8A
o 200-240V/4A
* DC output wattage: 300 Watts

Memory card reader

* USB interface
* Supports the following cards:
o Compact Flash I
o Compact Flash II
o SmartMedia
o Memory Stick
o Memory Stick Pro
o MultiMediaCard
o Secure Digital (SD)
o Micro Drive
o XD Picture Card (xD = extreme digital)