Compaq Presario CQ40-505la Windows XP Drivers

Net framework 2.0
Download

CHIPSET
INF Update Utility - Primarily for Intel® 5, 4, 3, 900 Series Chipsets
Download (direct link)
Download (intel website)
Download(mediafire)

GRAPHIC:
Mobile Intel 45 Express Chipset Family Graphics Driver
Intel graphic accelerator 4500MHD
Download

AUDIO: follow the instructions.
MS UAA (required with a reboot before Audio driver)
here:
ftp://ftp.hp.com/pub/softpaq/sp33501-34000/sp33867.exe

Audio driver: IDT High-Definition Audio CODEC Driver
(choose any download links below)
Download (HP)
Download (ftp)
Download (mediaifre)
Download (ziddu)

read the sound installation at the end of the post.

High-Definition Audio (HDA) Modem Installer and Driver
Download sp39545.exe

Windows Installer 3.1(required before wireless)
here:
http://tinyurl.com/9cg2y

If you have Intel PRO/Wireless Drivers
here:
Download

if you have Broadcom Wireless
here:
Download sp39243.exe
Download

ETHERNET:
Realtek RTL8102E Family PCI-E Fast Ethernet NIC
Download

CARD READER
JMB38X Card Reader Host Controller
Download

ENE-CIR Reciever:
Download

for HDMI Audio
ftp://202.65.194.212/pc/audio/HDMI-R203.exe

ALPS Touchpad Driver
ftp://ftp.hp.com/pub/softpaq/sp31001-31500/sp31075.exe

or try this new driver (not sure it will work)
ftp://ftp.hp.com/pub/softpaq/sp38501-39000/sp38629.exe

HP Quick Launch Buttons
ftp://ftp.hp.com/pub/softpaq/sp40001-40500/sp40139.exe

If you have Bluetooth,
HP Integrated Module with Bluetooth Wireless Technology
Download