
Microprocessor-board  connectors and LEDs
The following illustration shows the connectors and LEDs on the microprocessor board.
| 
 | 
 | Memory | 
| Light path diagnostics | Memory | card 2 | 
| Memory | ||
| button | card 1 | card 3 | 
| Fan 6 | Fan 3 | Fan 8 | 
| Fan 7 | 
 | |
| Fan 2 | 
 | |
| Fan 5 | 
 | Memory | 
| 
 | card 4 | |
| 
 | 
 | 
Fan 1
Microprocessor card error LED
Fan 4
| 
 | 
 | 
 | 
 | 
 | Microprocessor 3 | 
| Microprocessor 1 | 
 | 
 | 
 | 
 | VRM connector | 
| 
 | 
 | 
 | 
 | Microprocessor 4 | |
| socket | 1 | 2 | 4 | 3 | |
| 
 | 
 | 
 | 
 | 
 | VRM connector | 
| 
 | 
 | 
 | 
 | 
 | VRM 4 error LED | 
| 
 | 
 | 
 | 
 | 
 | VRM 3 error LED | 
| Microprocessor 2 | 
 | Microprocessor 3 error LED | |
| socket | 
 | Microprocessor 3 socket | |
| Microprocessor 1 | Microprocessor 4 error LED | ||
| error LED | 
 | ||
| Microprocessor 2 | Microprocessor 4 socket | ||
| 
 | |||
error LED
18IBM System x3950 Type 8878 and System x3950 E Type 8879: User’s Guide