Hello! friends:
     Today my computer won't work ,it shows "non-system disk or disk error
"when I boot it.In fact , it happened first several months ago ,but now it
happens more frequently . And I must cut off power for more and more times
to let it recognize the hdisk again and work fine ,I really don't know why
it can recognize hdisk sometimes and it can't sometimes.
 I repulg the jumpers on the hdisk(appears the ID setup) , but in vain .
the following is the condition of my PC:
brand:Compaq desktop XL 560
hdisk:50 pin scsi hdisk
mobo:scsi interface ,eide interface and floppy interface
Then I try to install another hdisk into EIDE interface ,but nothing new
happens ,it shows "non-system disk or disk error ".
So I try to enter into CMOS setup , but I can't do it .(all keys in
keyboard I 've tried)Then I see a  notice on the back of the machine box ,
it says "the 6th switch of SW1 ---- erase EISA configuration".
so I change it to status of "on " ,this time when I boot it ,it shows
"172 - configuration nonvolatile memory invaild
Intilization Aborted
Run System Configuration Utility
"F1 " resume                                      "

when I hit "F1" ,it reshows " non-system disk or disk error".
Now ,just now ,I can do nothing about it:
1.the old scsi hdisk won't boot
2.system can't recognize the new eide hdisk
BTW ,the floppy disk is ok to boot from and read and write .but when I turn
to c: , it shows " invaild partition ".
So my dear friends ,please help me out, much appreciation from me .

yours
david dwell