Ghetty Prime, also called G-Prime, is Mainframe's main industrial sector, as well as a place for some of Mainframe's less reputable citizens to gather. Al's Wait & Eat cafe is located there near the outer base of the Principal Office, on the feared Level 31.
When Mainframe's Twin City was destroyed the virus Megabyte arrived in Mainframe. He quickly began infecting Ghetty Prime, wanting it for its industrial buildings so he could build an army. On the outer edge of the sector he built his headquarters, a large tower named Silicon Tor, from which he ruled Ghetty Prime.
Megabyte used Ghetty Prime to stage several attacks on the Principal Office and on his sister, Hexadecimal, on the island of Lost Angles. When he stole the Medusa Bug from Hex, Ghetty Prime became the first sector to be infected by the small viral bug.
Megabyte's domination of G-Prime is extensive thanks to massive army of viral Binomes and ABCs. The Principal Office was only ever able to retake one of the sub-sectors that make up Ghetty Prime when Phong, Dot, and Bob eventually organized the retaking of one sector, registering its inhabitants with the Principal Office and being able to reformat the sector into an Energy Park. (Identity Crisis, Part 2)
During the Viral Wars, Phong and Mouse came up with the idea of putting an inverted firewall around Ghetty Prime to imprison Megabyte and Hexadecimal. They were successful, and for a time the viral threat was contained. Eventually Hexadecimal broke free of Megabytes control, destroying the Silicon Tor and overloading the firewall. During the battle between the two viruses Ghetty Prime was severely damaged, causing Megabyte to take the Principal Office as his new base.
When the system crashed and was later restored by the User, Ghetty Prime was restored and a viral scan removed the infection from it, erasing the Silicon Tor.
During the Net War, Ghetty Prime's industrial buildings were invaluable to the city in constructing forces able to fight off Daemon. When Megabyte returned, he established a make-shift base in its depths where he could set up the Gateway Command.