Help Amiga 500+ plus is missing 512 Kb ram / memory

[Junior]

Hi , i need some Help with my Amiga 500+ Rev 8A :

Last week i tested the Amiga with a 1 Mb Expansion and works fine but after a while playing a Demo and reboot the Amiga the A500 is missing 512 Kb of the standard 1 Mb .
The Amiga has only left 303200 bytes left in Workbench and when i use the command Avail only 512kb is showing in the list .

Proberly there is one on maybe more chips damage has anybody a idea ? ..

 

[demolition]

Did you turn it off completely when it was rebooted? Ctrl-A-A may not reset it properly.

 

[Junior]

Yes i did , swapt all possible Ic's like Agnus , Denise , CPU .

 

[alexh]

Reseat the RAM card?

 

[disco]

Couldn't hurt to clean the contacts with isopropyl alcohol and reseat the expansion.

 

[Junior]

There is no expansion connected , it's just the standard A500+ these has 1 Mb normaly but only 512kb is available .

 

[demolition]

Could be that part of the upper 512k died in a way that prevents it from being added as valid memory. If you insert the 1MB expansion again, do you then end up with 1.5MB?

Does your 500+ still have the battery installed? If it does, it could very well be what damaged your motherboard.

 

[Junior]

That was my idea too about the upper 512Kb , the weird thing is that i have two machines with this problem and 1 is adding the extra expansion so i have 1,5 mb and the other one does not recognize the extra Ram .

 

[demolition]

Well, the battery leakage problem is common for all 500+'s and even if the battery was removed at some point, the corrosion could continue to eat away at the tracks if it was not cleaned up 100%.