Trouble! pls help!

Just bought a Asus A7V8XX and i have been having troubles...

Had an old system and replaced the CPU and Motherboard.

Motherboard - Asus A7V8xx VIA Socket A
CPU - Atlhon XP 2500+

Old motherboard- Epox 8kha+
Cpu- Athlon 1.4

I was told i could just replace the mobo and Cpu and i would be fine.. wireless internet isnt working and wont let me install i get a message saying "not compatable software with windows XP" But i know it is.
i also tried to reinstall Windows..( no Format) and it didnt work.. Cant enter Bios Either i hit delete key all the way from startup and nothing.. but i can enter the Bios Flash (Alt+f2) any help would be much apprectaited if i need to list any more information pls let me know

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Didou

Welcome to TechSpot

Bad news for you. When you replace a motherboard, you have to re-install Windows from scratch, then install the mobo-specific drivers that come with that mobo.

The reinstall you did, was really a repair, which cannot function because of motherboard issues.

A bit further down on this page you will find the A7N8x-thread. In there is a whole lot more information about this mobo (albeit with nVidia).