90s Olivetti laptop

[Jazzburger]

I have this Olivetti echos p75 800 laptop and Im planning on to install windows 95 on it. But Im stuck in a sort of a loop with the machine. Seems like there is nowhere to boot from. When I exit the setup, the monitor does not receive signal anymore (it blinks cursor for 2 secs and then the screen goes black). This happens even when I dont change anything in the setup. Always black after exit from setup no matter what. Then I have to disconnect the battery and power cable, wait for couple minutes (have also tried wait 24 hours but no difference) and then the computer posts again when booting (picture 1). If I press F1, it gets stuck in this "Operating system not found". I have already replaced the old leaking cmos battery with a new coin battery. Also I have only Windows 95 OEM CD. There is cd and 3.5 inch floppydrive, but the system can only have one of those drives connected at a time. Here are the screens that I get when I turn the machine on. What can I do here?

 

[powerlot]

What type of battery was in there and what did you replace it with? You should not have the CMOS checksum bad message if you correctly replaced the battery (and cleaned/repaired eventual leakage and damage)
If the IDE autodetect doesn't work you either have a bad HDD or have to select the HDD type manually (but for this the BIOS needs to retain its settings)

 

[Jazzburger]

Thank you for reply. Ill put photo of the old and new battery here, there was minor leakage, almost none. This article says the old battery is 2,4V RTC battery https://oldcomputer.info/portables/echos75/index.htm. The new one is 3V coin battery I am trying to jam in there. I am starting to think the HDD is bad, it also makes some funky scratchy noises when booting.

 

[powerlot]

Hmmm, I'm not convinced this is a 2.4V battery, because it looks like 3x 1.2V = 3.6V. See Varta 3/V15H S DA for example. Someone else could confirm or deny this...

Additionally, did you solder in a diode, preventing the recharge current flowing back to the non-chargeable coin cell?

The hard drive could be shot, but if the CMOS settings aren't proper it can cause all kinds of random problems

 

[Brian Todd]

Looking at pic 2, it suggests that you have 4 hard drives, which cannot be the case as you have a laptop. On pic 6/7 it shows, however, 0 MB on IDE adaptor 0, which suggests the hard drive is toast... this being the case, I would expect that after you press F1 the screen goes black for a few moments and that you then get the "operating system not found" message. When you go into the BIOS (pic 6) and select IDE 0 master, what do you see? Also try to put the other three adaptors on auto and see what happens. Do you have a DOS floppy disk you can try to boot from?

Just a thought .. if you connect up the CDRom try to boot from the Windows 95 CD. You might have to change the boot order in the BIOS first, or at least see if the CDRom is enabled as a boot device.

 

[Jazzburger]

Hmmm, I'm not convinced this is a 2.4V battery, because it looks like 3x 1.2V = 3.6V. See Varta 3/V15H S DA for example. Someone else could confirm or deny this...

Additionally, did you solder in a diode, preventing the recharge current flowing back to the non-chargeable coin cell?

The hard drive could be shot, but if the CMOS settings aren't proper it can cause all kinds of random problems

You are right, it has to be that Varta battery. I was not familiar with this battery and the recharge. I should absolutely solder in the diode next and see what happens.

 

[powerlot]

Is the coin cell still good? Not sure how they react to recharge. I assume the old one was NiCd, but th new ones are NiMH. I would have replaced it with one of those NiMh batteries, but if it works with the coin cell without causing CMOS errors, why not

 

[Jazzburger]

Thank you for the answers! I am putting this project to a halt at this point, since the diode didnt work either. I think the board is not having fun with my coin cell contraption. I am trying to find right kind of battery locally and hope the hard drive is not completely dead.