Brightness set to 0% [Solved]

[Z0K4]

Hi Sabayon users... Just today I've downloaded the amd64 edition with gnome desktop and tried to install it to my system. When booting to LiveCD mod, my LCD just turns off... To be more accurate brightness is set to 0%, so I could not see anything and thus could not install it on my hardware.
My hardware specs:
Intel T4400 dual core processor,
Intel GMA 4500M integrated graphics chip
And it's eMachines laptop... I believe you don't need more hardware info for this problem! Does anyone have a suggestion?
Thank you!

[wolfden]

try adding acpi_osi=Linux for a cheat code, than use the fn key + whatever key to adjust brightness, my laptop does same, goes black on boot up

[Z0K4]

Thank you for your advice... but I'm either blind or the boot procedure is not the same for the 32 bit and 64 bit systems... I mean, when I'm booting live CD in virtualbox (32bit sabayon) at the beginning I can choose between many of the options... Here is the link to the capture:
http://oi42.tinypic.com/vdfm1j.jpg
But when I try to install 64bit there's only a black screen that says:
boot:
If i hit enter it starts booting and screen blacks out! That's cool with me... I waited 2-3 minutes and then right clicked and choose "open in terminal" (I did this blindly... I've already used gnome3 and know my way around) typed in
su
and because I was live user i figured it will not require any password. Continued typing:
setpci -s 00:02.0 F4.B=0
hit enter, and back light was back on, and brightness was set to 100%
I figured yaaayy... i'll be able to install it. Clicked the install button, and let it do the magic... when it came to the end of installation it required restart so I did it... but either there was something wrong with the installation or I did something wrong but the grub was messed up.
When it came to that point (entering grub2 or something like that) my laptop just continued rebooting, over and over, and over again... so I had to use my recovery disk and fix mbr to be able to boot to win7 (I need it for college)
So any thoughts about that? Is it the installation bug, or I did something wrong?

[wolfden]

is the md5sum good?

[Z0K4]

is the md5sum good?

Yes, md5 checks OK. I've double check it before installing, and just now. So the iso is not corrupted. I did try install Sabayon via usb (I've used universal USB installer... it went without errors) Could that be the problem, maybe it's not "adjusted" for sabayon 8!?