Question about Toshiba Satellite A100-S8111TD Notebook

1 Answer

0251: System CMOS checksum bad-Whats this? ToshibaA105-S4254

Dear All,
I have a 2 yr old Toshiba A105-S4254.No software problems so far (except for the power chord problem, now solved, which is pasted below). But,today For the fist time when I turn the power switch on I get a black screen and I get this message (among other things that are written):

0251: System CMOS checksum bad- Default configuration usedPress to load default to set up"

I have no idea what this is. Which of the two F1 or F2 should I press?
Thanks in advance,
PS: I have pasted the old probem which got solved last week below just in case it is related to this current one. Thanks

PREVIOUS PROBLEM that got magically solved on its own is given below:

Dear All,

Ironically, 5 days after the paid warrenty expired (2 years and 5 days after I bought this piece of equipment), the A105-4254, it suddenly died on me!

It always had a "loose connection" to the AC adaptor. While working at home, I always had to pull and yank the power cable everytime I used it to make sure the "blue power light is on" and that power is being supplied to my laptop or else it would indicate that it is being powered through the battery instead.I lived with it. However around Christmas, when it was the season to be Jolly, the power cable connection started acting up big time and I perpetually had to hold the powersupply cable connection to the laptop with my left hand and type using only one hand. This went on for a few days. And then, on January 17 2009, my laptop just died on me. Like dead dead.I bought a new powercord ($150)- nothing. I removed the battery and plugged in the AC adapter-nothing. No lights, no sounds, nothing. I cannot live without my laptop. Help.

Please give some suggestion which do not include paying an arm and a leg to get it repaired (it is outside the warrenty remember).
Thanks to all in advance,

Posted by on

  • shr8002 Jan 28, 2009

    Thanks DJSam. I will press F1 as you recommended.

    What exactly is CMOS?

    And I didn't do anything to my laptop in ternms of software, so then how did the "checksum" become "bad"? In other words, what could I have done to cause this? I only use my computer (toshipa laptop) to surf the internet and check emails etc.

    Thanks again,


1 Answer

  • Level 1:

    An expert who has achieved level 1.


    An expert who has answered 20 questions.


    An expert that hasĀ over 10 points.


    An expert whose answer gotĀ voted for 2 times.

  • Contributor
  • 32 Answers

You can go ahead and press F1. If it happens again the next time you boot up or it just goes back to that screen try pressing F2 and then exit with saving.

This should solve your problems, If it doesnt you have something configured incorrectly in the CMOS.

If this is the case there should be somewhere that you can restore the defaults of the CMOS (as every computer is different I can't guide you through this process)

Have a great day.

Posted on Jan 28, 2009

  • djsam112 Jan 28, 2009

    CMOS - complementary metal-oxide semiconductor

    It is the chip that holds all of the information for the BIOS.

    It is basically the base workings of the computer on how it runs all the hardware.

    I apologise for neglecting to state this in my last response but if it keeps happening this could be due to your internal battery (looks almost like a watch battery) going dead.

    Another thing that can cause this is a faulty BIOS install or a program that changes settings in your BIOS. As updating the BIOS can be a risky procedure i would recomend getting someone confident in this to do it for you. (Do this only if it is the problem)

    So again if this keeps happening it is most likely the internal battery that powers the CMOS chip as you have already stated that it is most likely not due to software.


1 Suggested Answer

  • 1124 Answers

SOURCE: A105-S4254 is dead!

According of your description, If you already changed the power suply, and the battery, and still no signs to power on, your laptop has some issue at power connector in the motherboard and need to be serviced.

Posted on Jan 24, 2009

Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

1 Answer

I want to restore my Toshiba Satellite Pro to factory Settings, and I don't have the recovery CD.... The specs: A105 Processor: Intel(R) Core(TM)2 CPU T5600 @ 1.83GHz Memory (RAM) 32-bit Operating System...

Set BIOS defaults
  1. Press the [F1] key.**** Bad RTC battery ****
    **** Bad Checksum (CMOS) ****
    Check system, then press [F1] key
  2. In the BIOS setup screen press the [Home] key to restore the default values, then press the [End] key to save and exit, then the [Y] key to confirm and restart the system.

If you need more help come back.Post / thumbs / testimonial are welcome!

Nov 27, 2010 | Toshiba Satellite Pro L300-EZ1005X...

3 Answers

I want wireless driver for a105-s4244


Thanks for using FixYa. You can download the drivers forToshiba A105-S4244 from the link---

ToshibaA105-S4244 Drivers

Please do rate the solution and revert for furtherassistance.



Nov 18, 2009 | Toshiba Satellite A105-S4244 Notebook

2 Answers

IBM Thinkpad will not hold date & time.

Replace the backup battery and run BIOS Setup Utility to reset the time and date. This will resolve the issue.

Sep 15, 2009 | IBM ThinkPad T22 2647 Notebook

1 Answer

Got this error message WARNING 0251: system CMOS checksum bad. Default configuration used. Then everything went black. Can't find the wireless network (altho it IS working on other computer in the...

this sounds like a bad flash, when you went to update the laptop did you happen to download any bios firmware updates? if so it;s a bad flash and will need to be reflashed to fix it.

Aug 22, 2009 | Gateway M320 XL Notebook

1 Answer

Toshiba continues to reboot

The motherboard is faulty - there is nothing you can do to fix it. You could take it to a Toshiba service centre to get a quote, but it is likely to be nearly as expensive as a new one... sorry :(

Aug 20, 2009 | Toshiba Tecra A4-S313 Notebook

3 Answers

Turn on computer and message reads ****bad check sum (CMOS) ****

That means that after computer had been off for a long time the CMOS battery has drained, and CMOS (BIOS) settings had been reset to default.

Usually the computer will work fine after pressing F1, but you may get wrong date and time.

Try charging battery completely, often the problem disappears, if it does not , then the choice is between pressing F1 each time you start the laptop, or disassembling the laptop and replacing CMOS internal coin battery, located on the lower side of the motherboard.

May 17, 2009 | Toshiba Satellite 1805-S204 Notebook

1 Answer

Toshiba Satellite M45-S169 won't boot

you must restore your bios settings to the correct ones. contact toshiba customer support for the correct toshiba settings.

Jul 27, 2008 | Toshiba Satellite M45-S169 Notebook

2 Answers

BIOS Resetting...

Please open this link this will help you

And dont forget to rate FIXYA if it didnt help please reply but dont rate any rating

May 03, 2008 | Toshiba Satellite A105 Notebook

1 Answer

Blue Screen

Try re-starting your pc and tapping the F8 while it starts up and try getting in through "Safe Mode". If you can get in click "Start", "Run" and type "cmd". Hit OK. At the dos promt type "sfc" and let windows check your files.

Apr 10, 2008 | Toshiba Satellite A105 Notebook

Not finding what you are looking for?
Toshiba Satellite A100-S8111TD Notebook Logo

2,590 people viewed this question

Ask a Question

Usually answered in minutes!

Top Toshiba PC Laptops Experts

Brian Sullivan
Brian Sullivan

Level 3 Expert

27725 Answers


Level 3 Expert

5660 Answers

john smith

Level 2 Expert

366 Answers

Are you a Toshiba PC Laptop Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides