Report Success replacing Capacitors on Cube Motherboards

Started by Rob Blessin Black Hole, October 24, 2013, 01:45:51 AM

Previous topic - Next topic

Rob Blessin Black Hole

Hello NeXT Community:

This is designed as a template to be added to  help catalog known motherboard booting errors on NeXT cubes and if replacing capacitors, with new ram fixes the error and she boots!

Recently I went through my inventory on Cube motherboards at least forty hours not counting capacitor replacement labor.

Separating working from non working boards .

The non working Cube Mother boards spawned various errors or had different problems

I wound up with 10 motherboards which we replaced the capacitors on.

If your system was working and it throws the following errors replacement caps resolved this :

1: 68030 25Mhz 1988 GOLD Board version 1.0 rom  was freezing on boot
New caps boots beautifully

2: 68030 25Mhz 1988 GOLD Board version 1.0 rom was giving bogus stack error and coupling error, new caps and change out ram booting like a champ

3: 68040 25Mhz 1989 Green board version 1.0 rom had loose bios battery connection causing intermittent boot , resoldered bios battery holder with new caps boots perfectly

4: 68040 25Mhz 1989 Green board version .42 rom CPU error , new caps boots perfectly

5: 68040 25mhz 1990 Board 1698 Version 2.2 rom 1991   Exception #2 error  new caps and ram boots perfectly

6: 68040 25Mhz 1990 Board 1698 Version 2.4 V66 rom flakey network  boot hang error , new caps boots perfectly

No luck with these so far:

7: 68040 25Mhz  1990 Board V2.1 Wont power up , new caps , new bios battery still won't power up ? Any thoughts thinking power connector at bus , bios battery connection to board or pin and video cable connecting

8: 68040 25Mhz 1990 Board Ver 2.1 won't access bios , new caps stuck on loading from network tried swapping in different version 2.1 rom set to verbose boot system froze only power key works

any ideas?

9: 68040 25Mhz 1990 Board Ver 2.1 no video , new caps  tried swapping in different version 2.1 rom and version 2.4 set  powers up

thought bad video connection or bad vram chip

any ideas?

10: 68040 33Mhz 1990 Board bios unknown may be protoype board says software error reports as 25Mhz processor , I may try and swap processors.


My tech Charles does very professional work at a reasonable price so basically we have a new service to offer fresh caps .  He also works on Amigas and early macs and was referred by another forum member.

His charge to me is $45 a board and $10 cap kit with shipping both ways.

So to keep the lights on here if anyone is interested I'm sure we can come to an agreeable rate.  My time to handle the logistics and accounting, paypal fees etc as he prefers to go through me so he can focus on repairs is worth X to you.

As I have loads of regular NeXT motherboards you may just choose to pick one of those as a replacement but in the next 5 to 20 years probably all NeXT motherboards will need new caps to function as they eventually leak.  

At any rate it is very cool to have like new boards now as well , we can also replace caps on working motherboards !

Hope that helps someone determine if caps will resolve problem!

Best regards Rob Blessin
Rob Blessin President computerpowwow ebay  [email protected]
303-741-9998 Serving the NeXT Community  since 2/9/93


Hi Rob,

Do any of the nonworking boards have blink codes? That's a good place to start. Also, in my opinion, every board should be recapped at this point (cube or nextstation). I have yet to see a case where there wasn't some form of degradation on the caps. By the time you see a leak, the chances of corrosion causing a board level issue increase greatly. Your price seems fair to me for those who are unable to do it themselves.




thanks for sharing this information. I was able to fix two Next Cube cpu boards by  replacing its capacitors. In one case I had to replace only the four large ones and the board was working again. In the other case (a turbo board) I had to replace all including the small smd capacitors.