N9030B PXA Signal Analyzer Service Guide 279CPU/Disk Drive TroubleshootingA4 CPU DescriptionProvisions have also been made to allow the CPU board to remember whichpower state it was in when a power failure occurs. The instrument will return tothe same power state after a power failure.Rear Panel ConnectivityThe A4 CPU board assembly has direct access to the rear panel of theinstrument. The external connections provided on the A4 CPU board assemblyinclude:— External VGA— LAN (RJ45) 10/100/1000 based-T Ethernet port— USB— 4 x Type-A ports (USB 2.0 compatible)— 1 x Type-B port (USB 2.0 compatible) Instrument behaves like a USBdevice (client)— GPIBSystem MemoryThe type and amount of system RAM in the instrument may vary depending onthe age and options installed in an instrument.Current instruments will have 4 GBytes of DDR SDRAM in two 200-pinSODIMM memory modules.While the memory controller chips do support a wide range of DDR memorytypes, only memory fully qualified by Keysight Technologies is supported. Fullqualification includes mechanical vibration and shock, thermal and powerdissipation and the basic electrical characteristics.The 200-pin SODIMM memory modules are not field replaceable.All replacement A4 CPU board assemblies come with the appropriate memorymodules installed.System ProcessorThe A4 CPU board assembly uses an Intel Pentium-M series processor chip.CPU BatteryThe LI-ION battery powers the instrument clock and maintains the settings forthe CMOS BIOS configuration. Keysight changes the boot order setting so theinstrument disk drive is first. If the battery fails, the boot order reverts to theUSB first. Therefore if a non-bootable USB device is connected when theinstrument powers up, a black screen with a message such as: “Failure: Nobootable partition in table” will result and may cause the user to believe theinstrument is faulty.
