|Even when the battery IS too weak or dead or is not being recognized properly for whatever reason, the bios will retain the custom settings you make in it until the AC power to the computer has been removed, or at least until after Windows or Dos has been shut down.|
All AT family computers switch off the AC power to the AT power supply when you switch off the case's power button.
All ATX family computers still have power to some places on the mboard when the system has been shut off via the case's power button, if the ATX power supply is still receiving live AC power.
If you have to set the hard drive to a non-default setting when the time and date are set to bios defaults, replace the cmos battery ! !
Of ALL the mboards I've fiddled with that had the ability to set the date and time in the bios, XT and up, maybe a hundred mboards, there was ONLY ONE that could not retain the date and time and yet could retain other custom settings AT ALL TIMES when there was nothing wrong with the bios detecting the cmos battery properly. It was a Hsing Tech early Pentium mboard, sold retail as the PCChips model M500. That happened only after the mboard had been used about 5 years or more
If that's your situation, if your mboard DOES NOT have a RTC module (see response 6), your mboard is defective and there's absolutely nothing you can do about that !
If your mboard DOES have the RTC module, you need to replace it (it must be ordered off the web and is not easy to find), or carefully open it up from the top of it and and connect a non-rechargable battery of the same voltage (3.0 ?) to the leads for the tiny dead battery inside of it.
For older bios versions....
- they can have known bugs that make the bios version incapable of detecting a hard drive larger than ~ 2.1 gb (~2,150 mb) properly, as seen in the bios, which usually sees the drive's binary size, not the hard drive manufacturer's (decimal) size.
- or the bios version may be incapable of doing that because of limitations of the main chipset on the mboard.
For the former, in some cases someone other than the mboard manufacturer has made a custom bios update that allows all hard drives up to and including 137 gb hard drive manufacturer's size to been seen as their full size (137 gb hard drive manufacturer's size = ~128 gb in most bioses and ALL operating systems).
Tell us the make and model of your brand name system, or if you have a generic desktop system, the make and model of the mboard.
The specific model of a brand name system is often shown on a label on the outside of the case somewhere, or it can often be determined by going to the brand name's web site and loading a program they have available, if Windows is still working, on the subject computer.
If it's a Dell computer...
Go here for how to find the Service tag "number":
Tell us what it is.
If it's a HP or Compaq computer.....
Scroll down a bit.
Look for the similar label on the outside of your computer.
Quote the specific model number - that's at the end of the first line.
Quote the Product number - that's on the third line.
If it's a Lenovo computer
Find your specific Product number and tell us what it is:
Finding my product number
The model, sometimes the make, of a mboard in a generic desktop system is usually printed on the mboard's surface in obvious larger characters, often between the slots.
Some mboards have no model number printed on them - those that were in a brand name system computer, and some retail models.
Hsing Tech sold / sells their mboards wholesale to other vendors who sold it / sell it under their own model number. Hsing Tech mboards usually DO NOT have a model number printed on the mboard surface, but they have a unique bios string that identifies them as a Hsing Tech mboard. Many ECS models that have no model number printed on the mboard are actually Hsing Tech mboards.
If the mboard has no model number
- if it was in brand name system, we can usually find info about the mboard if you supply the proper brand name model it was in.
- if it was a retail model in a generic system,
If Windows is working (this may not work in Win 3.1 ).....
Go here, download BIOS AGENT.
Run BIOS AGENT to find your bios string.
- here's the link that downloads Bios Agent
The current Bios Agent calls the bios string the Bios ID.
Tell us the Bios ID it finds, or everything Bios Agent finds, and include any dashes, etc.
Bios Agent must be used in Windows.
The following works even if you have no drives at all connected to your mboard but you are able to boot and get a display on your monitor.
If you cannot use Bios Agent, the bios string is usually a long string of numbers/letters at the bottom of the first black screen as you boot your computer - it often begins with a date - usually you can press the Pause key to read it and copy it down.
Press any key but Pause to continue booting.
It could also be higher up the screen under or beside the bios version line, e.g. under or beside Award or AMI or Phoenix...
Post that bios string here, and include any dashes, etc.
Please make sure you copied it right. Most Award and AMI Bios strings do not have spaces. Newer Phoenix bios strings, based most often on those for Intel mboards, are often like so: xxxxxxxx.xxx.xxxxxxxxx