A4000T Problem

[Bokasa]

My A4000T stopped working with A3640. Also working perfectly with A3630. At the other side, A3640 working perfectly with other Amigas? What could be problem? Thanks!

[nishtek]

J100    Pins 1 and 2    CLK90 Clock Source is Internal
   Pins 2 and 3    CLK90 Clock Source is External
J104    Pins 1 and 2    CPU Clock Source is Internal
   Pins 2 and 3    CPU Clock Source is External

external for 68040. so 2-3 on both J100/J104.

this is based on your statement : a3640 works fine in your other amigas.
Other than that, the socket is ok on the a4000T, but maybe the 3640 connector is worn? only qualified service man can fix that.

[Bokasa]

Well... Jumpers are ok, and clear situation is:
1) A4000T can't work with A3640... I have three A3640 and Amiga can't work with any of them...
2) All my A3640 working with other Amigas... (4000D)
3) A4000T work fine with different A3630 (030, EC030, with or without FPU)

[José Manuel]

You have installed the 68040.library in libs?

[Akiko]

It could also be timing issues caused by leaking caps, I once had a 4000 that went bad, it worked with the standard 030
but wouldn't boot with a T-REX 060 plugged in, eventually it also stopped recognizing certain Zorro cards.

[Bokasa]

It could also be timing issues caused by leaking caps, I once had a 4000 that went bad, it worked with the standard 030
but wouldn't boot with a T-REX 060 plugged in, eventually it also stopped recognizing certain Zorro cards.

timing issues?

[Zac67]

Leaked caps cause more noise eventually leading to bus glitches, especially when a 'beefier' CPU pulls more load.

[Bokasa]

Leaked caps cause more noise eventually leading to bus glitches, especially when a 'beefier' CPU pulls more load.

And what can I do? BTW, I changed caps at the end of 2011. . .

[Zac67]

Then you can rule out the caps, I suppose. Have you checked the PSU voltages and possibly ripple?

[Erol]

May be obvious question, but have you cleaned all the connectors?
Just because it works on another Amiga you may have dirty connectors.

Also what revision is the A3640?  as A4000T needs revision 3.2  although it will work with older revision.  This cards are prone to overheating as well.  

The A4000T (Tower) also has a crap fan,  i would recommend replacing this with a more powerful fan.

[Bokasa]

May be obvious question, but have you cleaned all the connectors?
Just because it works on another Amiga you may have dirty connectors.

Also what revision is the A3640?  as A4000T needs revision 3.2  although it will work with older revision.  This cards are prone to overheating as well.  

The A4000T (Tower) also has a crap fan,  i would recommend replacing this with a more powerful fan.

Well...
1.PSU is OK... Working perfect with 3630+16M Fast Ram+Scsi HDD+Scsi CD+IDE ZIP
2.I dont know how to check ripple
3. Revision is 3.1
4. I have two fan, both new + fan on 040 CPU.

Thanks for help.

[Erol]

Well...
1.PSU is OK... Working perfect with 3630+16M Fast Ram+Scsi HDD+Scsi CD+IDE ZIP
2.I dont know how to check ripple
3. Revision is 3.1
4. I have two fan, both new + fan on 040 CPU.

Thanks for help.

Your welcome.
I just checked my A4000T manual and there are different jumper settings for using a 30 card or 40 card.  both are different.
Have you sent the correct jumper settings?

[Erol]

Also clean the connectors on the A3640 card with some alcohol and cotton bud.
if the capacitors are faulty on that card, you can contact analogic they do amiga repairs.
they actually repaired my A4000T when i accidently damaged the board.

http://www.analogic.co.uk

[Zac67]

Another thought: the standoffs need to be exactly the correct height - if the CPU board isn't exactly parallel the contacts can be bad.

You can measure DC ripple by setting your multimeter to AC voltage, the lowest setting available (2V or lower). For somewhat reliable values you'll need a true-RMS meter but you should be able to get an idea with anything sensitive enough.