Technical Reference 
 65 
2.7.2.2  Add-in Card Connectors 
The board has the following add-in card connectors: 
•  Primary PCI Express x16 (electrical x16 or x8) bus add-in card connector; one 
connector supporting simultaneous transfers up to 8 GBytes/sec 
•  Secondary PCI Express x16 (electrical x8) bus add-in card connector; one 
connector supporting simultaneous transfers up to 4 GBytes/sec  
•  PCI Express x16 (electrical x4) add-in card connector; one connector supporting 
simultaneous transfers up to 1 GBytes/sec.  This connector can also be used for PCI 
Express x1 add-in cards. 
•  PCI Conventional (rev 2.2 compliant) bus; two PCI Conventional bus add-in card 
connectors. 
Note the following considerations for the PCI Conventional bus connectors: 
•  All of the PCI Conventional bus connectors are bus master capable. 
•  SMBus signals are routed to both PCI Conventional bus connectors.  This enables 
PCI Conventional bus add-in boards with SMBus support to access sensor data on 
the Desktop Board.  The specific SMBus signals are as follows: 
⎯  The SMBus clock line is connected to pin A40. 
⎯  The SMBus data line is connected to pin A41. 
2.7.2.3  Auxiliary Front Panel Power/Sleep LED Header 
Pins 1 and 3 of this header duplicate the signals on pins 2 and 4 of the front panel 
header. 
Table 28. Auxiliary Front Panel Power/Sleep LED Header 
Pin Signal Name  In/Out  Description 
1  HDR_BLNK_GRN  Out  Front panel green LED 
2 Not connected     
3  HDR_BLNK_YEL  Out  Front panel yellow LED