EEE PC 1000 Win7 BIOS

[njefferies]

Can someone on here please help me.
I know that this involves a rather old Netbook, but it suits my needs perfectly, if i can only get it to work.
I have an ASUS EEE PC 1000, not 1000h, or 1000ha, or 1000 anything else.
It originally came with Linux and has two SSDs.
I replaced Linux with XP, and everything has run perfectly for many years.
I have upgraded the BIOS to version 1003 which is the last BIOS that ASUS did for this model.
I now want to install Windows 7 on this, but there are no BIOSes available that are for this model and Windows 7. I have tried but cannot install a BIOS from any similar model no matter how i try to fool the system.
BIOS 1003 does not have any option to turn on AHCI mode, and even though i have succesfully installed Windows 7, it is running unbelieveably slowly because the SSD is in IDE operation.

Can anyone please hack a BIOS so that i can runAHCI in Windows 7 for thie model of EEE PC.

Many, many thanks