Service Manual
Page 38
... another DIMM is not available, replace the memory option. The specific error is programmed into the code overlay card. Checksum Failure. Unrecoverable software error in slot 1. Note: Service errors 980 thru 984 can reflash NAND. Replace the system board. 961 RAM in Slot 2 is Bad If another SDRAM memory DIMM is experiencing unreliable communications to "Disabling Download...
... another DIMM is not available, replace the memory option. The specific error is programmed into the code overlay card. Checksum Failure. Unrecoverable software error in slot 1. Note: Service errors 980 thru 984 can reflash NAND. Replace the system board. 961 RAM in Slot 2 is Bad If another SDRAM memory DIMM is experiencing unreliable communications to "Disabling Download...