All drivers shold be listed on Hp website. Take a look a it. Surely it has to do with chipset drivers. Also, if you can describe your problem would help us to help you
My Computer
Computer Manufacturer/Model Number
HP a6720f
OS
7 Ultimate x64 RTM 7600.16385
CPU
AMD Phenom 9550 @ 2.20ghz
Motherboard
Asus M2N78-LA
Memory
4x2GB DDR2 Patriot Viper 800mhz
Graphics Card(s)
GeForce 9400 GT 512MB
Sound Card
Onboard Realtek Hi-Definition ALC 888S chipset
Monitor(s) Displays
Samsung P2370HD 23" 1080P HDTV
Screen Resolution
1920x1080
Hard Drives
Western Digital 640GB; Samsung 1 TB; WD 500GB; Seagate Portable 250gb;