pc doesn't startup - please help

[GB]

Hi to all
my siemens pc doesn't boot, it follow the step for to find a bootable
unity (cd floppy or hd), but it stops when it have to control the hd to
boot, so it wait with a black screen and a flashing cursor.
i've read about this probloem that could be a mbr problem, like MS
suggest, but i've used the fixmbr utility without success!
i've tried to disconnect the peripherals like printer, usb pen, etc.
i've tried with unplug from power the mobo
at end the pc still wait with the blank screen
the pc run good when i use a knoppix cd for boot, from here i can read
the disk and open files
the hd is ide, the processore is celereon 1200 with 512MB ram, is a very
simple pc, no lan connession
what can i do?
thank' for suggest

Giorgio

 

[GB]

kony ha scritto:

Has any part of the system been changed since it last booted
properly? I mean either hardware or bios? The system is
now getting older so if your motherboard battery is dying it
could have lost the CMOS settings for the correct boot
device. Check the battery voltage with a multimeter if you
have one, check whether the BIOS system clock is keeping the
right time and date, and if it isn't, replace the battery.
If the battery needs replaced, next go into the bios menus
and make sure the correct settings are set for the hard
drive to be detected and the preferred boot device.

Does the system boot ok to a bootable floppy or CD?

One common cause for this is a failed hard drive, you might
run the hard drive manufacturer's utility disk to see if the
drive is ok. Also check the drive cables, replace a
parallel ATA cable if you have a spare and if SATA, unplug
and replug it carefully in case it isn't making good
contact.

Instability can also sometimes make the system stop just
prior to booting, especially capacitor failures in the PSU
or on the motherboard. Inspect the motherboard and if all
else fails, leave the PSU unplugged for a few minutes then
open and inspect it.

Do you have a reason to believe the system was infected with
a virus? If not, it seems less likely that there is a
problem with the MBR. If all else fails, try putting
another hard drive in that system or putting that hard drive
in another system to see if either combination works.

thank's a lot for suggestions
i've tried some of these and i can made this:
-i can boot from cd or floppy, the pc run well with knoppix live cd
-i've unplugged the PSU both from mb and power network
-i've unplugged the hd, the cd/dvd from from ide cable and the cable
from the mb
- the battery is ok, the clock in the bios is right
- i'm not sure to be clean from virus because the AntiV isn't update but
i've used the pc some days ago with no problem
-i'haven't changed nothing in the hardware, i use only a usb pen that
sometime a leave plugged

but at last
- i've tried with another hd with win2000 and the pc boot from hd!!
so i suspect that is a problem with the mbr/ntldr/ntdetect files, this
evening i try to replace the files with the correct from the winxp cd

i hope
many many many thank's
Giorgio