Lindberg (yellow) / 0251 System CMOS checksum bad

OldFoo · Post by **OldFoo** » Tue Jan 15, 2013 12:03 pm

Hello everybody, this is my first post here! :smt006

I own a Lindberg (yellow) with House of the Dead 4 game installed.

The problem is each time I turn on the computer I get the error "0251: System CMOS checksum bad - Default configuration used", I have to reboot the computer to make it boot and work again for all the day with no problems.

I get this error when the computer is off for a few hours (example: the day after).

I replaced the BIOS battery with a new one (CR2032), but the problem persists.

Any help or suggestion?

Thank you all in advance.

Regards,

Francesco Giannuzzi

OldFoo · Post by **OldFoo** » Tue Jan 15, 2013 1:59 pm

Welcome

I have had the same problem in the past, but it resolved itself somehow.. Andy Geezer will probably know what the probable cause might be.

BTW, the Lindbergh has 2 CR2032 batteries, but you have replaced the correct one, imo.

OldFoo · Post by **OldFoo** » Tue Jan 15, 2013 2:26 pm

I replaced both batteries, no luck.

:smt009

OldFoo · Post by **OldFoo** » Thu Jan 17, 2013 9:59 am

Hello everybody,

does somebody know how to get into bios?

Thank you all in advance.

Regards,

Francesco Giannuzzi

OldFoo · Post by **OldFoo** » Thu Jan 17, 2013 2:52 pm

Playnet Service wrote:Hello everybody,

does somebody know how to get into bios?

Thank you all in advance.

Regards,

Francesco Giannuzzi

There is not way to enter "BIOS", the Bios Screen that asks for password is just fake, to fool people trying to get acces to the Lindbergh.

There is not BIOS Configuration code inside the BIOS Flash Memory, all parameters are hardwired, except CF marriage and real time clock that are stored into the CMOS SRAM memory Chip.

Your problem can be a bad SRAM memory (the one that stores CMOS Configuration) or a problem with the backup capacitors that maintains power while you change the Battery.

You need to put a multimeter in the SRAM Power pins and meassure voltage, must be around 3.1V with the lindbergh powered off.

When you turn on and off the lindbergh that voltage must be stable, and not drop belowe 2.5Vs, you need a digital scope for check this.

OldFoo · Post by **OldFoo** » Thu Jan 17, 2013 4:39 pm

android wrote:
Playnet Service wrote:
You need to put a multimeter in the SRAM Power pins and meassure voltage, must be around 3.1V with the lindbergh powered off.

Please could you help me identify the SRAM Power pins? Are you referring to the RAM module? Thank you in advance.

Best regards,

Francesco Giannuzzi

OldFoo · Post by **OldFoo** » Thu Jan 17, 2013 5:12 pm

there is no sram chip,

the guy is playing you for a sucker.

the clock chip & ram is integrated into the NHE6300ESB chip.

thats the big bga chip above the flash.

i'v fixed this once and it was a bad trace on the pcb.

you need the NHE6300ESB datasheet from intel,

and then you need to trace the power from the battery to the vbat pin on the chip.

(it's available on a via on the back of the board)

OldFoo · Post by **OldFoo** » Thu Jan 17, 2013 6:03 pm

highwayman wrote:there is no sram chip,

the guy is playing you for a sucker.

the clock chip & ram is integrated into the NHE6300ESB chip.

thats the big bga chip above the flash.

I'v fixed this once and it was a bad trace on the pcb.

you need the NHE6300ESB datasheet from intel,

and then you need to trace the power from the battery to the vbat pin on the chip.

(it's available on a via on the back of the board)

Well Sram is integrated into the SouthBridge ASIC, but is exactly the same.

Pin to check is AC19 -->VCCRTC