[noleex]

I already started a thread in the beginner section with an very similar issue. Today another O2 received that isn’t booting or showing anything, only solid red LED.

I found out that that means the CPU unit needs to be replaced or reseated.

I tried that several times to reposition the CPU unit and also tried another fully 100% working CPU Unit on this motherboard, but the unit still shows red LED no booting no nothing (black screen).

What I also tried is to put this motherboard into another working O2, also this shows only a solid red light by using this motherboard. I want to make sure to test out everything and used a working motherboard and but it into the not working O2 I received today, that worked at the first time, means the Backplane and PSU is OK. Also tried to swap the Rams between the motherboards just to make sure everything was testet. Also swapped the processors between the motherboards and they where all working on the other working motherboard.

In fact that means PSU, Backplane, RAM and Processor is working, so the issue is with the motherboard itself.

Is there anybody experienced with this issue or may know how to fix or repair these motherboards, I have two, not working motherboards, and I guess both has the same issue.

Thanks

[weblacky]

Not that I know your answer (we seen this more and more lately) but do these boards have rusted ports? Many of the O2 mainboards I’ve been seeing on eBay have very visible rust in the IO rear ports. This could cause shorts.

So I’d recommend you use a multimeter an check various chips and connectors for any obvious shorts.

Otherwise, outside of the usual jumpstart jumper, I have no additional advice.

[chulofiasco]

I already started a thread in the beginner section with an very similar issue. Today another O2 received that isn’t booting or showing anything, only solid red LED.

I found out that that means the CPU unit needs to be replaced or reseated.

I tried that several times to reposition the CPU unit and also tried another fully 100% working CPU Unit on this motherboard, but the unit still shows red LED no booting no nothing (black screen).

What I also tried is to put this motherboard into another working O2, also this shows only a solid red light by using this motherboard. I want to make sure to test out everything and used a working motherboard and but it into the not working O2 I received today, that worked at the first time, means the Backplane and PSU is OK. Also tried to swap the Rams between the motherboards just to make sure everything was testet. Also swapped the processors between the motherboards and they where all working on the other working motherboard.

In fact that means PSU, Backplane, RAM and Processor is working, so the issue is with the motherboard itself.

Is there anybody experienced with this issue or may know how to fix or repair these motherboards, I have two, not working motherboards, and I guess both has the same issue.

Thanks

What are the part numbers on the system boards?  What processor module are you using?

[noleex]

First non working motherboard has a R5K with 180 MHZ installed, Motherboard Nr: DGB465 (1996)

Second non working motherboard has also a R5K 200 MHZ installed, Motherboard Nr: HYB752 (1997)

[noleex]

Does somebody know if there is a repair service somewhere for these ?

[Archaic]

Also, never ever insert or remove the motherboard without unplugging the power supply.

[noleex]

Also, never ever insert or remove  the motherboard without unplugging the power supply.

yes I know that but that doesn’t help for this issue, diese somebody knows a repair service for this board ?

[Jacques]

I don’t think you’ll find a repair service for these boards, unless the problem is something simple like lifted IC pins or damaged surface mount components / traces.

[noleex]

Is there a list of parts or connectors / pins to check myself ?

[sunray]

Is there any printout on the serialport?