Reading BIOS chips (2 x MX25L6473E) with CH341A Programmer & Software

@Lost_N_BIOS - Thank you for you prompt attention.
This is all new to me, so I may not understand some of your terminology.

When I clicked on your 1st link, I get this error message:
‘Vodafone Content Controls: Access blocked, You won’t be able to access this page because it’s been blocked by your content control settings.’

Q1: What is it for?

When I originally purchased & installed this Gigabyte GA-Z87-HD3 mobo,
its BIOS Version was: F4 / Dated: 16/05/13
Later, I downloaded & installed their latest (at that time) Firmware,
eg: BIOS Version: F7 / Dated: 20/01/14

The F7 BIOS was working OK until about a year ago, when the mobo would no longer boot.

My mobo has 2 BIOS chips (2 x MX25L6473E)
on the board they are labeled M-BIOS & B-BIOS

I don’t know which is the master/backup and which the board normally runs from?
The bin file I sent you was from B-BIOS

Q2: Do I have to ‘repair’ both of them?

If the M & B stand for Main & Backup, then my bin file was from the BACKUP.
Q3: So do you need a bin file from the MAIN ?

Q4: Is this my mobo’s MAC ID ?
This 12 digit number was on a label on-top of the LAN metal block: ************

Many thanks.