Mega Chip showing 512k?

[Greywolf12]

I just installed a megachip plus in an 2500 rev 6.2 and its only showing 512k.  tried the lead on the 68000 and Gary(5719), take the megachip out put the Agnus 8375(318069-17) back in I get 1meg.  Made sure all jumpers are correct.

Any Ideas

Grey.

[fiat1100d]

What is the code of the Agnus chip installed on the MegAChip?

[Oldsmobile_Mike]

I have installed MegaChip's in both my A500 and A2000 with no issues. So we understand correctly, your system is showing 1MB of chip before installing it, but after installing it you're only showing 512K? Can you post a photo of the top of the board, with it installed? The lead should go to the Gary chip and you may want to check your jumpers.  Can you confirm the MegaChip is working correctly in any other systems?
 
There are installation instructions here that might help:
 
http://amiga.resource.cx/exp/megachip