Unlocking Aspire 9800 BIOS

[iserver]

Hi everybody. I'm trying to install Win 8.1 on my old Aspire 9800 and it falls on booting from CD with black screen, but Win 7 boots normaly. So I wanted to ask if there is any way to update / mod my bios ? And I don't know why, but Acer decided to hide AHCI mode enabling in this bios. Is it possible to enable this function ?

[iserver]

Oh. Just right now found topic about almostly the same model Aspire 9810 - link. So it looks like - there is no way to fix my problem...

[iserver]

One more question. Is is possible to change vbios in this bios ?

Aspire 9800 has integrated 7300 Go card with vbios ver. "5.72.22.32.18"

I used phoenix tool (Phoenix/Dell/EFI SLIC Mod v.2.58) to update VBIOS in bios image.

I found 3 variation of VBIOS on techpowerup.com
VBIOS for 7300 Go

So, decided to use "5.72.22.46.57" cause it was latest build as I understood.

After unpacking BIOS image, I found that VBIOS for my card is located in OPROM01.ROM block, so I replaced it with new ROM (remaining the same file name). But after flashing BIOS image - I got BLACK screen, so I had to use crisis disk to restore BIOS back. Any ideas what am I doing wrong ? Shall I change any values in other bios blocks before flashing ? There are some strings in BIOSCOD3.ROM about VBIOS, but I don't know - shall I change them ?

P.S

First of all I tried NvFlash for flashing VBIOS, but it says - "supported EEPROM not found".

P.P.S

Thanks for any advices

[iserver]

Hi Guys ! ) Anybody home ? I found that screen goes black cause of whitelist in file BIOSCOD3.ROM.

Is there any utility for patching it, to make BIOS work with updated VBIOS, or is it possible to patch it with hex editor ? Anybody knows ?