RE: Precision T5500 Pb7 Error
1100 Watt power supply is required. You have a smaller power supply.
flashes the Pb7 error code, which translates to:
ACPI S0, hand off to BIOS control
System on. BIOS not execution. This is the transition state to POST states.
Solid Amber — System fault(Motherboard), but +5VSB Power Supply is good—normal operating state (S0)
BIOS must be updated BEFORE changing CPU.
Pb7 is dead motherboard/cpu