|"The default CPU freq in BIOS is now set to 200.....l"|
Do you mean 200mhz cpu speed or cpu core frequency or fsb frequency? That info is not useful to us unless we know what brand name system or mboard you have.
When you remove the battery then replace it, the bios is set to defaults, and you usually do not have to change anything (other than the date and time the first time) in the bios Setup in order for the cpu and ram to be found properly automatically.
"an odd window with only a warning icon "
Describe what it looks like.
Make sure your keyboard and mouse are properly plugged in before you try booting. PS/2 connected mice and keyboards are NOT "hot pluggable" - DO NOT fiddle with their connection while the computer is running. If they were not fully plugged in, they usually won't work again till after you reboot in any case.
It's common for wires inside corded cables to mice and keyboards to become damaged - you could try unplugging those to see what happens.
"Last night my system froze & when I rebooted I got this message: "Please re-setting CPU frequency in CMOS" "
Some bioses display a message like that if
- something interrupts the normal POST sequence during the boot - e.g. you pressed the key to get into the bios Setup too soon in the boot sequence - if you are prompted to go to the bios Setup or automatically go there, you merely save bios settings and reboot, then everything works fine again if there's nothing else wrong.
- you have some hardware problem, such as an iffy ram connection in it's slot(s), or a defective hard drive or optical drive - whther or not you are prompted to go to the bios Setup or automatically go there, you save bios settings and reboot.
If you still have problems after that, you investigate possible causes e.g.
- an iffy ram connection in it's slot(s) ?
A common thing that can happen with ram, even ram that worked fine previously, is the ram has, or has developed, a poor connection in it's slot(s).
This usually happens a long time after the ram was installed, but it can happen with new ram, or after moving the computer case from one place to another, and I've had even new modules that needed to have their contacts cleaned.
See response 2 in this - try cleaning the contacts on the ram modules, and making sure the modules are properly seated:
For a laptop, you must remove both its main battery and AC adapter before you do that.
- for a desktop computer, a data cable connection problem ?
It is common to un-intentionally damage IDE data cables, especially while removing them - the 80 wire ones are more likely to be damaged. What usually happens is the cable is ripped at either edge and the wires there are either damaged or severed, often right at a connector or under it's cable clamp there, where it's hard to see - if a wire is severed but it's ends are touching, the connection is intermittant, rather than being reliable.
Another common thing is for the data cable to be separated from the connector contacts a bit after you have removed a cable - there should be no gap between the data cable and the connector - if there is press the cable against the connector to eliminate the gap.
80 wire data cables are also easily damaged at either edge if the cable is sharply creased at a fold in the cable.
Try another data cable if in doubt.
Check your SATA data cables. The connector on each end should "latch" into the socket on the drive and on the mboard, or on the drive controller card - it should not move when you merely brush your hand against it near the socket - if it does, mere vibration can cause a poor connection of it - use another SATA data cable that does "latch", or tape the connector in place.
(There is a slight projection or bump on one side of the outside of the connector that "latches" it into the socket - it's easily broken off or damaged)
The same thing applies for the SATA power connection.
- for a desktop computer, a power supply problem?
Check your PS.
See response 4 in this:
If it is failing, you can usually replace it with any decent standard sized standard ATX PS with the same capacity or greater.
Standard (PS/2) power supply size - 86mm high, 150mm wide, 140mm deep, or 3 3/8" h x 5 7/8" w x 5 1/2" d , or very close to that, though the depth can be more or less for some PSs.
- your hard drive Windows is booting from is failing?
Check your hard drive with the manufacturer's diagnostics.
See the latter part of response 1 in this:
(thanks to Dan Penny for this link:)
Hard Drive Diagnostics Tools and Utilities
If you don't have a floppy drive, you can get a CD image diagnostic utility from most hard drive manufacturer's web sites, but obviously you would need to make a burned CD, preferably a CD-R for best compatibilty, on another computer if you need to.
If the hard drive itself tests okay, any data problems found can be fixed, one way or another.