Amiga 4000 problems

[amigakid]

I am stumped!  I have been trying to get my old A4000 up and going.  I bought another MB from Ebay (second one now) and all I get is a Red Screen immediately when it turns on.  I don't remember but I thought there was a second or two delay when it powers on before the system check begins.  I know Red means ROM problem, but the red screen comes on right when the power button is pushed, absolutely no delay.  Also I have swapped them with 3.1 and 3.0 ROMs and still same thing.  I am not sure but could the PSU be a problem?  It is actually the only thing I don't have a spare of and the only common factor ... actually not true the CPU board is also the original, but I get the red screen when it isn't even connected.  Ant suggestions would be great as I am tired of spending money on MBs and still not have a working A4000

[amigakid]

Also the CTRL+A+A does restart the Amiga ....kind of, when I have the HDD connected it spins up and the HDD light comes on for a sec and when I CTRL+A+A the HDD restarts, but the screen stays constant red, not even a flicker!

[amigakid]

Yeah that was my initial thought!  I shall try the U871 chip, never thought of that.  Thanks for the replies I'll keep you all posted on if I get it fixed

[amigakid]

OK so initially I had the monitor on digital so I was getting the colored screen.  On RGB the screen is a dark grey when it turns on.  If I remember right the A4000 starts with that screen for a second the changes to a lighter grey then does the system checks.  The screen doesn't change at all so I am thinking it isn't making it to the post.  Could this be the PSU causing the issue?  The HDD light does come on briefly and the CTRL A+A does seem to restart the unit (hdd spins down then back up, but power light or screen does not flicker at all).

[amigakid]

OK After testing the PSU (which seems to be alright) I inspected the 3640 processor card and noticed 2 of the caps have leaked.  Anyone know where I can get replacement caps, or anyone have a working processor card they are willing to part with?

[amigakid]

The red screen was because I had the monitor on digital lol.  Thanks for the site link I will take a look there.  I been looking on Ebay for a replacement CPU, but haven't found one yet.

[amigakid]

Yes they are an unfortunate design.  I have an Amiga 500+, 1000, 3000, cd32 and 2500hd and I have never had this much issues with any of them lol, but I am not giving up until she is up and running good.

[amigakid]

wow seems you had quite a bit of experience with them, that is great.  Yeah hopefully I can find a used, working CPU card for it.  I will buy and replace the caps and hopefully get this one up and running also!.. Thanks for all the input!!

[amigakid]

Yeah I loved the A4000, prob my favorite, although I do really like my A3000 setup I have too.  I wish I had a working CPU card because I have some software I been wanting to run and it is my only AGA box