Use 4164 RAMs in place of 4116 RAMs The 4116's used in the early Apple IIs run very hot and are fairly unreliable. They require +5v, +12v, -5v and 0v for power. We can actually adapt a more common 4164 RAM so it will fit into a 4116 socket. This RAM runs much cooler, requiring +5v and 0v only, and tends to be more reliable. Let's have a look at the pinouts of the 2 types: ___ ____ ___ ____ -5v -|1 \_/ 16|- Gnd N/C -|1 \_/ 16|- Gnd Din -|2 15|- /CAS Din -|2 15|- /CAS /WE -|3 4 14|- Dout /WE -|3 4 14|- Dout /RAS -|4 1 13|- A6 /RAS -|4 1 13|- A6 A0 -|5 1 12|- A3 A0 -|5 6 12|- A3 A2 -|6 6 11|- A4 A2 -|6 4 11|- A4 A1 -|7 10|- A5 A1 -|7 10|- A5 +12v -|8 9|- +5v +5v -|8 9|- A7 --------- --------- OK, well the data pins are all in the correct places but we'll need to do something about the power supply pins which are needed for the 4116 but not the 4164. Also, the 4164 has 4 times the capacity of the 4116 so we'll need to address that too. This turns out to be really easy, the A7 pin of the 4164 is in the same place as +5v on a 4116, so we don't need to do anything here and A7 will be tied high. Pin 8 of the 4164 (Vcc) will be connected to +12v unless we do something about it. We bend the pin so that it won't go into the socket and jumper it to +5v - the easiest way to do this is to connect it to pin 9 on the other side of the chip. The surplus length of the bent pin 8 can be snipped off. Finally, pin 1 of the 4164 should not be connected to anything but will be connected to -5v if placed in the socket for a 4116. We can simply snip off this pin and all is well. This procedure can also be followed to use a 41256 as a 4116. Also in the IIe 80 column/64k card, you can bend up or remove pin 1 of a 41256 to replace a 4164. I have one with 2 such chips inserted and it works fine. I also have a II+ with a chip such as described above and no problems. If you need to or simply want to try this, and are not sure, simply email and I'll walk you through it. Thank you for reading. This page has been formatted for People using Apple IIs accessing the internet.