my PC keeps rebooting. When i turn on the pc, nothing shows up on
the montior, not even the bios beep. i checked and tried
everything like removing the ram chip and checking for the beeps
and stuff .... in short, i have checked all the basic steps one
usually does to check for problems.

all the fans are working fine. i have 810chipset with onboard
sound and graphics card, 1 pci lan card and 1 amr modem.
processor is p3-500 slot based, 256mb sdram(1 chip),20 gb hdd.

i dont think even power supply (not the comp power supply,... i m
talking about the socket in which we plug our computer), coz i
have a spike-guard. other devices such as mixer-grinder,
refrigerator work fine on the same power supply. actually i have
shifted my pc to kitchen from the past few days on a temporary
basis, but it worked fine till date (from 3 weeks).

one more thing i would like to say, uhhhh,..... everytime i start my pc (from the past few months) this error mess would be displayed "Please re-select the cpu speed" inspite of all setting being correct. It would ONLY start after i goto bios > exit without saving > yes. weird .....

Hi, rahulkothari.

That error message makes me wonder? How old is this computer? have you changed the CMOS battery? The forgetting settings looks like a battery problem, and if all the settings are gone, then it might well do just as you have described. Incidentally, even with a spike protector, electric motors can still cause a noisy supply.

David

my pc is 2 yrs old , havent changed cmos battery, will do it soon.

but even if the cmos battery is gone, it should work.

does anyone know what(& where) is the jumper setting in 810 for resetting the bios ? ... i mean we have to short few pins in order to reset it ... and also, how do we detect whether the processor is fried or not ?

Hi Rahul,

Each motherboard has it's own location for the jumper to reset the BIOS. Which motherboard do you have?

And yes, it could be that your processor is going. The only way I know to test a processor is to try a different one and see if it clears the problem. Do you know anyone who would lend you a processor?

It's really helpful to have a pile of spare parts around for trouble shooting.....:)

thx everyone for replying. this is weird, i replied to this post before few hours and the reply aint displayed.

anyways, this was to inform that i changed cmos battery, and the pc worked fine,..... no error messages ...... not even the one (plz reselect cpu speed) that bugged me from few months.

but i still dont understand, why the comp refused to start at all, coz the battery was out from months ?

The reason a PC can't boot properly without a good CMOS battery is because all the vital information about all the hardware is stored in CMOS and only stays there as long as power is applied, while the system is off, power is applied by the battery. If the battery goes dead all of the information is lost such as CPU type and speed, hard drive type speed and size, and RAM type, speed, and amount installed PCI and AGP cards installed and their IRQs and all of the settings in BIOS settup revert to the defaults stored in EEPROM. When you boot without this data stored in CMOS the BIOS doesn't know what hardware it has for its use or how to use it. The reason you need to enter BIOS settup save and exit is each time you do this the data is written back to CMOS and the DMI data pool is updated and you are good to go until you turn the PC off than the whole thing starts over with no data in the CMOS. Without a good CMOS battery the CMOS is volatile and is cleared each time the PC is turned off just like system RAM.

The reason you need to enter BIOS settup save and exit is each time you do this the data is written back to CMOS...

it was exit without saving. :confused:

... the DMI data pool is updated and you are good to go until you turn the PC off than the whole thing starts over with no data in the CMOS. Without a good CMOS battery the CMOS is volatile and is cleared each time the PC is turned off just like system RAM.

so pc SHOULD work without battery, coz as i mentioned above, my pc was without any battery (it was there in the socket, but was uncharged) and it worked smoothly(albeit with exit without saving) for months and all of a sudden it refused to start at all. :confused:

i hope someone would reply to my (now)boring post. :(

P.S.: hope "how does this work ?" section starts again ... :rolleyes:

It was either not as dead as you though or you were turning on th emachine often enough to keep the settings (there are capacitors and the natural tendency for CMOS RAM to slowly discharge that could have kept it going for short periods of time....I have seen it take upto 12 hrs to discharge by pulling the battery in an attempt to reset the settings.)

ok... got it, mjc .... thanks. :)

I would like to thank all of you as i really learned a lot, reading the forums in vacation. But i dont think i would be able to read it all now, coz college is about to start, but would definitely "payback" by replying to whichever simple threads possible, whenever i get time.

straight from heart

:) hope my new college wont be strict and i could bunk enough. ;) :D