MP All Models 820-2337-a

[Tara laptops]

pls can anyone provide technical information for 820-2337-a board.
In all i have 4 boards. In 2 boards all lights, power supply , fans , graphic card fan gets on fine but on display.
In two boards nothing get on. when i press the diag led switch one orange led blinks for once.
Pls share the technical information. Also i find totally 4 bios. 1- U8700 , 2- UB301, 3-UC650, 4- UB201. Any idea what each does. Pls reply. Thanks

 

[tsialex]

The only SPI flash memory that really matters is U8700, the BootROM. Use the search and learn about it, no need to re-write it again here.

SPI flashes UB301 and UB201, near the right corner, over and underside of the board, are for the firmwares of the two Intel Ethernet controllers. These two don't affect boot ability.

UC650 is SMC related, I think that this flash is where the SMC keys are stored, it's a AT24C512B.

 

[Tara laptops]

i have two boards. I reprogramed the bios. It gets on but the cursor stops on the apple logo in both the boards. Cpu , power supply and the graphic card are confirmed ok. Any idea pls