|"Yes Removing battery is first thing we do"|
Okay, but you didn't answer....
Is this when the the AC adapter is plugged in, or whether or not it is ?
"all the lights are fine"
In all cases, even when you get no video ?
"....my laptop boots some time and some time it does,
mostly on weekends it works fine,
on satuday and sunday it boots on first try and on monday i think i should give it to garbage wala.
some time it boots on monday , so i cant really say when it will boot."
Should that have been....
my laptop boots some time and some time it does NOT ...
The day has nothing to do with your problem, other than coincidence.
If the leds ALWAYS come on even when you have no video, you will probably find that if you connect an external monitor you will always have video, at least while booting BEFORE the operating system loads.
If the leds DO NOT always come on when you have no video, you probably have a problem related to your main battery, or the AC adapter, or the connection of the AC adapter's cord to the laptop's jack, or the jack in the laptop the AC adapter connects to.
"i thought it might be the OS issue ..."
A problem with the software on the hard drive has NOTHING to do with whether you have video while booting BEFORE the operating system is supposed to load. No video before that point can ONLY be caused by a hardware problem.
If the operating system sometimes loads fine and you have video in that, there's probably nothing wrong with the operating system's software.
Side note - you CAN have problems with the computer coming out of Standby or Hibernate modes, or Restarting, if you DID NOT install the main chipset drivers for the mboard after Setup was finished, especially with XP and older.
"...I Flashed Bios by downloading the bios of my laptop form lenovo site. i put the serial no. of it then i got the bois os this laptop."
It sounds like you probably got the right bios version for your model, however.....
- it MAKES NO SENSE AT ALL to flash your bios if the computer worked fine with the bios version it had AT ANY TIME before you had your present problems - in that case, the bios version it previously had was working fine !
- after you have flashed the bios with a different version, you should always load bios defaults in the bios Setup, because usually flashing the bios DOES NOT clear the previous contents of the Cmos part of the bios chip, and it's likely the changed bios version won't work correctly until you have done that.
Otherwise, bios versions either work properly or they don't - they DO NOT sometimes work properly, sometimes not work properly.
Laptop no video (or video problems), and battery, AC adapter, power jack T shooting.
See response 1:
If there is nothing wrong with your AC adapter or it's connection and the jack in the laptop.......
Laptop main batteries usually work as they should for a year or so, then they begin to
rapidly deteriorate. From what I've seen, by two years they cannot be charged to anywhere near their full capacity, and it gets worse after that.
They often develop internal shorts when they are older. If the battery gets HOT rather than just warm after you have attempted to charge it for at least a half hour, or after you have been using the laptop for a while with the AC adapter plugged in, it's definitely internally shorted and you must replace it. Internally shorted batteries getting too hot have been known to cause the laptop to catch on fire.
Tips about battery charging problems on Dell laptops - may apply to other makes.
See response 3 in this by iTech: