GPT Hard Disk Drives for HP Business Desktops
5 
The BIOS Characteristic Extension Byte #2 is described in Table 1. Bit 3 of Byte 2 
specifies UEFI specification support. 
Table 1. BIOS Characteristics Extension Byte 2 
Bit Position  Description 
0  When set, BIOS boot specification is supported 
1  When set, function key-initiated Network Service boot is supported. When 
function key-initiated Network Service boot is not supported, a network 
option ROM may choose to offer this functionality on its own, thus offering 
this capability to legacy systems. When the function is supported, the 
network adapter option ROM shall not offer this capability. 
2  When set, enables Targeted Content Distribution. The manufacturer has 
ensured that the SMBIOS data is useful in identifying the computer for 
targeted delivery of model-specific software and firmware content through 
third-party content distribution services. 
3  When set, UEFI specification is supported. 
4  When set, the SMBIOS table describes a virtual machine. When cleared, no 
inference can be made about the virtuality of the system. 
5:7  Reserved for future assignment by this specification. 
The user can determine if the system has a UEFI BIOS by looking for the splash 
screen during boot referencing a top-level Startup menu (Figure 3). 
Figure 3. Splash screen of HP UEFI BIOS system 
The startup menu (Figure 4) can be accessed by pressing the Esc key during the 
boot sequence. 








