Gigabyte GA-P55M-UD4s Vs. Gigabyte GA-P55M-UD2s

Operating System, Form Factor and Processor

Supporting the Microsoft Windows 7, Vista and XP operating systems, each Gigabyte GA-P55M-UD4 and Gigabyte GA-P55M-UD2 uses the Micro Advanced Technology eXtended, or microATX, form factor. Thus, each motherboard measures 9.6 by 9.6 inches, or 244 by 244 millimeters. Both components are based on Intel processor technology: a Socket 1166 that physically and electronically connects Intel Core i-series processors to the board and an Intel P55 Express chipset; the motherboards are actually partly named after the chipset. The P55 provides six Serial Advanced Technology Attachment connectors for the desktop's hard drives, used for data storage and accommodating optical discs such as CDs and DVDs.

Based on third-generation Double Data Rate Synchronous Dynamic Random Access Memory architecture, or DDR3 SDRAM, each Gigabyte GA-P55M-UD4 and Gigabyte GA-P55M-UD2 has two dual in-line memory module slots for the desktop's system memory. The DIMM slots can hold up to 16GB of RAM, with a maximum access speed of 2,200MHz. Each motherboard has four Peripheral Component Interconnect slots for expansion cards such as graphics processing units or sound cards. However, the UD4 has one regular PCI port and three more advanced PCI Express ports, while the UD2 has two PCI and two PCI-E ports.

Each Gigabyte GA-P55M-UD4 and Gigabyte GA-P55M-UD2 motherboard offers a 7.1-channel high-definition audio driver from Realtek: the ALC889A codec from the UD4 and the older ALC888B from the UD2. Accompanying the codec is a Sony Philips Digital Interface, with Dolby Home Theater support added on the UD4. The motherboards also provide an Ethernet connection for local area networking from Realtek: the RTL8111D, which has a peak data transfer speed of 1,000 megabits, or one gigabit, per second.

The Gigabyte GA-P55M-UD4 and the Gigabyte GA-P55M-UD2 provide a host of external interfaces at the desktop PC's back panel. They include six audio jacks, RJ-45 port for the Ethernet, IEEE -- Institute of Electrical and Electronics Engineers -- 1394a port and two PS/2 connectors for the computer keyboard and mouse. The UD2, however, has one more USB port than the UD4; the former has 10 ports while the latter has nine.