ASUS F5R - Bios modification and memory issue

[Holymanus]

Hello fellows, 
im new in BIOS modding, but not so new in HW and programming, so i will try to describe my problem as good as i can.

1.
Recently i bought IDE/PATA (CD/DVD replacement) to SATA. I connected it, together with HDD or SSD inside, to IDE. 
Then when turning my laptop on, after POST, booting process stops on "Auto-Detecting Pri Master". 
After about 2:30 min it gets through and quickly boot to OS. 
It is obvious problem is in detecting SATA device in IDE slot. 

What i would like to find out is, how to change BIOS to skip or to simplify process of detecting of Primary master from devices connected inside. 

2. 
Second issue is about memory mapping. Im using 2x 2GB, CPU and Chipset should be able to map whole 4 GB of memory. But bios shows about 2.5GB of memory and 128 MB shared as video memory (same with 1GB+2GB), Windows says 3GB installed and 2,47GB usable. It seems that one of slots doesn't use all available memory. 
My suggestion is that it is limiting is BIOS, but maybe im wrong and limiting is HW. 

Can anybody help me with these issues ? 

Im using (probably) the latest bios version 505 (attached) and i replaced CPU T2370 with T5300.

[Holymanus]

I figured out how to extract Bios Module but how to modify if?
Which tool do i need to modify AMI Bios Module?