The Z88 has 32K of internal RAM. This is not enough memory for every day use.

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Choosing a memory chip that works with the Z88 is important. Manufactures and the availability of chips change. See Memory Chips for the most 'up-to-date' results.

RAM chips

There are 3 types of RAM chips that may be used either Internally or Externally.

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There are some RAM chips that according to the application or data sheets should work, but don't. They are only found by trying them and the reason why they don't work will remain unknown.

PCB Footprint Converters

To aid construction, these converters may be used to allow the new surface mount devices to be used as larger devices. Let's face it, DIL or DIP packages are a lot easier to handle and solder. These converters may be used to 'bridge that gap.' Here are some examples:-

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Internal or External?

Changing the RAM or the ROM inside the Z88 is a time consuming and skilled operation. Unless the user has good soldering experience, changing chips in a 25-30 year electronic device can lead to killing the Z88 altogether. Let's look at the advantages when a successful conversion has been achieved first.

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	Amplia un cartucho de Z88 hasta 512Kbytes - Convert 32K RAM card to 512K RAM The memory chip described in the article above is no longer available. Suitable replacements are listed below.
	ALLIANCE MEMORY - AS6C4008-55SIN - SRAM, 4MB, 2.7V-5.5V, 512KX8, SOP32 Note: This has not been tested. It will probably fail.

Internal RAM (fitted on the Motherboard)

The internal 32K of RAM is not large enough. Upgrading this to 128K or 512K internally is possible, but the original 'built-in' OZ operating system did not use this correctly.

Cambridge Computer commissioned OZ 4.0 ROM and were planning to use this with the new User Guide v3 but only the User Guide was changed. The new ROM was made available to users through the Z88 User Group.

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