Compaq Presario CQ40-115AU windows XP driver

Install .Net Framework before others
Download

GRAPHIC DRIVER
ATI Radeon HD 3200 Graphics/Video Driver
Download (sp39764.exe)
or directly from amd site here:
Download

AUDIO
MS UAA (required with reboot before Audio driver)
Download

IDT High-Definition Audio CODEC Driver (copied from Microsoft Update Catalog)
Download (mediafire)

Audio installation instruction:
Unzip to a folder.
From Device Manager,right click "Audio Device on High Def Bus",choose Update driver,

No to connect,

Install from a list or specific location,

Choose search for the best driver in these location, Browse to the extracted folder.

Next - up to finish and Reboot.

Realtek RTL8102E Family PCI-E Fast Ethernet NIC
Download (direct download) or
Download (realtek site)

or miror below
Radarsync

or (copied from Microsoft Update Catalog)
Download (mediafire)

ALPS Touchpad Driver
ftp://ftp.hp.com/pub/softpaq/sp25501-26000/sp25796.exe

Modem:
High-Definition Audio (HDA) Modem
Download
if modem above didn't work try below
Download

Quicklaunch Button:
Download

ALPS touchpad driver
Download

ENE CIR receiver driver
Download

Note: if audio driver above didn't work you may try this audio driver
ftp://ftp.hp.com/pub/softpaq/sp41001-41500/sp41500.exe