VOGONS


First post, by idan182

User metadata
Rank Newbie
Rank
Newbie

Hi all
Retro AT computer with a CF adapter and weird problems.

I've changed 3 caps on the motherboard and it was working ok for some time.

Problem is, the CD drive + Hard disk working on the same IDE cable.
CD is the secondary master, sometimes it does recognize on bios and sometimes not.
The HD does the same sometimes.
It's not getting power from the button the first time. I can't hear the HD spins until I turn off and on the button again.

When it does spin, it gives me weird letters on bios.
I've tried to replace the ide cable, disconnect the master ide with the cf adapter but nothing.

Is it a bad motherboard or maybe a bad AT PSU?
The PSU looks fine inside with good caps.

20220909_135425.jpg
Filename
20220909_135425.jpg
File size
1.63 MiB
Views
268 views
File license
Public domain

Reply 1 of 11, by konc

User metadata
Rank Oldbie
Rank
Oldbie

The PSU might look fine, but is it? It's old enough that you should make sure it is.
I'd try the cdrom and hdd alone (as master device) to see if one of them has an obvious problem. Also use another molex to power them.

Reply 2 of 11, by Ydee

User metadata
Rank Member
Rank
Member
idan182 wrote on 2022-09-09, 11:03:

Problem is, the CD drive + Hard disk working on the same IDE cable.
CD is the secondary master, sometimes it does recognize on bios and sometimes not.

How can I understand it? Same = 1 cable for both (HDD+CD drive) devices? Then HDD must be set as MASTER and CD as SLAVE. Primary or secondary , it depends on which IDE port they are connected to - IDE 0 as PRIMARY, IDE 1 as SECONDARY.
If CD drive is set to SECONDARY MASTER, then must be connected on another cable to IDE1 port onboard.

Reply 3 of 11, by idan182

User metadata
Rank Newbie
Rank
Newbie

CF adapter is Primary master.

Cd is secondary master which is not recognized.
Mechanical HD is secondary slave.

I just notice that if I turn the computer on, either the mechanical HD, CD or Fan of the cpu is not working until the second power on.

They are all on 1 molex cable with an extension.
I have disconnected the cd, now everything works.

Maybe the PSU is weak?

Reply 4 of 11, by konc

User metadata
Rank Oldbie
Rank
Oldbie
idan182 wrote on 2022-09-09, 11:37:

They are all on 1 molex cable with an extension.
I have disconnected the cd, now everything works.
Maybe the PSU is weak?

Everything can be the culprit.
The cdrom might be problematic, the psu might be problematic or weak, the load on one cable with extensions might be too much (have you tried removing the slave hdd instead of the cdrom?)
We can't guess any further, you'll have to start eliminating possibilities. Try another psu, measure the psu, try the cdrom on another computer, remove the extension and use different cables as much as possible...

Reply 5 of 11, by Ydee

User metadata
Rank Member
Rank
Member
idan182 wrote on 2022-09-09, 11:37:
CF adapter is Primary master. […]
Show full quote

CF adapter is Primary master.

Cd is secondary master which is not recognized.
Mechanical HD is secondary slave.

I just notice that if I turn the computer on, either the mechanical HD, CD or Fan of the cpu is not working until the second power on.

They are all on 1 molex cable with an extension.
I have disconnected the cd, now everything works.

Maybe the PSU is weak?

It could be weak PSU, as you think. So on this IDE cable you have CD drive on one end (set as MASTER) and HDD on middle (set as SLAVE), cable is connected to IDE1 port, right? If so, then try set both CD and HDD to MASTER and try each one separately, if it works and recognized good.

Reply 6 of 11, by waterbeesje

User metadata
Rank Oldbie
Rank
Oldbie

Maybe the problem could be the CD is master and HDD is slave and expects an active ATA master.

Could you set the HDD to master and to the end of the cable, the CD to slave in the middle of the cable?

Stuck at 10MHz...

Reply 7 of 11, by idan182

User metadata
Rank Newbie
Rank
Newbie

All this caused by this molex extension !!
I could see that the fan is not starting unless I play with the 2 wires from the connector.

Replaced it to a fresh one and everything works again!

20220909_195727.jpg
Filename
20220909_195727.jpg
File size
850.9 KiB
Views
178 views
File license
Public domain
20220909_193645.jpg
Filename
20220909_193645.jpg
File size
1.3 MiB
Views
178 views
File license
Public domain

Reply 8 of 11, by Sphere478

User metadata
Rank l33t
Rank
l33t

Good job!

I was going to guess maybe your drive firmware had gone bad but looks like you figured it out! 😀

Sphere's PCB projects.
-
Sphere’s socket 5/7 cpu collection.
-
SUCCESSFUL K6-2+ to K6-3+ Full Cache Enable Mod
-
Tyan S1564S to S1564D single to dual processor conversion (also s1563 and s1562)

Reply 11 of 11, by Ydee

User metadata
Rank Member
Rank
Member
idan182 wrote on 2022-09-09, 17:01:
All this caused by this molex extension !! I could see that the fan is not starting unless I play with the 2 wires from the conn […]
Show full quote

All this caused by this molex extension !!
I could see that the fan is not starting unless I play with the 2 wires from the connector.

Replaced it to a fresh one and everything works again!

20220909_195727.jpg

20220909_193645.jpg

Ups, now it is clear - loose contact. You have to push the molex all the way, even if it's hard to do. Look at the gap between this and yours.

Attachments

  • molex.jpg
    Filename
    molex.jpg
    File size
    128.28 KiB
    Views
    109 views
    File license
    Fair use/fair dealing exception