A4000 - coming back to life

[Harrison]

As you have already done a full cap replacement I don't think it would be worth sending the board, unless you really can't find the issue. An alternative would be to ask on Amibay as many members on there will have some more ideas to what problems might be, and some might even offer to take a look for you for free, especially if I asked them on your behalf.

When you say the system is unstable, what exactly does it do? Will to boot to the kickstart screen? And if so does it boot into Workbench? Is it an 040 installed? If so it might be getting hot and over heating. I had that issue when I first replaced the original 030 in mine with an 040. I added a small fan on top of the heatsink and it solved the issue. One of the best ways to check the A4000 is stable is to boot up Frontier: Elite 2 and leave it cycling around on the intro. That really pushes the system and will see how stable it is.

[Tiago]

Well i am not the one who is doing all the stuff, it's Jorge Pedro from Coimbra.
I think that after a while it start to shut down... It is a 040 and it does not have a fan on top of it, but it was not an upgrade.
next saturdar we will try to change some more stuff, if it's not ok i will start asking everyone for help. but the fan could be a good thing to do.

[Harrison]

My A4000's 040 isn't an upgrade version either. Mine is the standard 3640 A4000 CPU board. My A4000 had the 030 version originally so I upgraded it to the standard 040 version. They still overhead, especially if they don't have the cooler 040 revision fitted. 040's are the hottest running CPUs from the 68K series and often having issues.

[Tiago]

we didn't do that yet, but i think it's a good test, putting a heatsink. Everythink looks fine, but after some minutes image freeze.
We changed RAMS, PSU, ROMS, PAULA, almost all CAPS.
He has his own 4000 so he swap a lot of parts, maybe try to swap the 3640+cpu just to see what happend.

[Tiago]

Some more news about this A4000, my friend changed some more chips on the baord, and it's now working good !!!!!!!!
He was able to run some games, without problems, only a few noice on sound left channel, but that should be a a result of to much heat with solder iron near the CAPS when fixing other stuff. So i am very happy with the results.... He is not a tecnician but he has good solderig skills, he replaced a lot of components from the board and we see now some very good results.

[Harrison]

No sound from the A4000 is normally the Caps right next to the audio out connectors. Replace those and it normally fixes it.

[Tiago]

Yes, he did replace them, it was the first thing he did, i did saw that process. But it was not enough, he start to replace other components, and in the end, there was to much soldering iron fo sold, and to much of that de-soldering unit of hot air. so the caps near the working areas must be replaced again.