Amiga 500+ freezes after clicking on icons

Hi!
At first I want to say hello to everyone from forum. I'm new here but my adventure with Amiga starterd in 1999 when I bought A1200 and Quantum 80mb HDD and 4mb fast with 020/28Mhz card. After about 10 years I sold my retro collection and don't think about it so that these days, when I became happy owner of two Amiga 500 plus.
One of them is working exellence, but with second I have a problem.
It is rev.8a mobo with 2.05 Kickstart, Rtc and battery was changed to Lithium Cr2032. Mobo has 2mb Chip Ram (8 chips soldered over 8 standard chips).
When I turn it on, everything is OK until I insert disk with WB and after I open Df0: Window and click on any program's icon, sometimes nothing happens. If I now click on Close window button, system freezes and I must reinsert disk. After this Amiga start to load program automatically. It not occurs when I click on drawers icon, only programs.
I check mobo with two other floppys, exchange both CIA, Paula, Gary, Agnus, CPU, ROM, Denise from my working A500plus with the same result.
Yesterday I recap mobo with new electrolityc caps. Amiga still freeze. I don't see any damaged tracks or vias, RTC is working good
Maybe someone have any suggestions what can I check, because I have no idea what is wrong.
Thanks
Chris

[kipper2k]

Hi,

I am guessing bad ram, get yourself a memcheck program and run it to see if it reports any errors, let it loop for a while to see what happens once the chips warm up, touch the top of the ram chips to see if one is unusually hotter than the other.

[Sandro]

Originally Posted by Chris__

Hi!
At first I want to say hello to everyone from forum. I'm new here but my adventure with Amiga starterd in 1999 when I bought A1200 and Quantum 80mb HDD and 4mb fast with 020/28Mhz card. After about 10 years I sold my retro collection and don't think about it so that these days, when I became happy owner of two Amiga 500 plus.
One of them is working exellence, but with second I have a problem.
It is rev.8a mobo with 2.05 Kickstart, Rtc and battery was changed to Lithium Cr2032. Mobo has 2mb Chip Ram (8 chips soldered over 8 standard chips).
When I turn it on, everything is OK until I insert disk with WB and after I open Df0: Window and click on any program's icon, sometimes nothing happens. If I now click on Close window button, system freezes and I must reinsert disk. After this Amiga start to load program automatically. It not occurs when I click on drawers icon, only programs.
I check mobo with two other floppys, exchange both CIA, Paula, Gary, Agnus, CPU, ROM, Denise from my working A500plus with the same result.
Yesterday I recap mobo with new electrolityc caps. Amiga still freeze. I don't see any damaged tracks or vias, RTC is working good
Maybe someone have any suggestions what can I check, because I have no idea what is wrong.
Thanks
Chris

which version of workbench disk are you using? plz note that workbench 1.3 and older versions are very sensible to clock and timing issues
if the 7mhz clock is not clean, workbench freezes when you click icons etc