Hi Hans-Erik, Jon;
I have an HP34C and I have opened (and successfuly closed) some solderless Spice's. What I can tell you is that if you look at it with the display in the upper position, all IC's are lined with their terminal (pin) #1 facing up (all of them, including the bigger one).
There are three places where you can mount the small 8-pin DIP IC's. The upper one is the only one that is kept fed while the calculator is switched to off (continuous memory). This is the place where the RAM IC must go. If you place a ROM IC in this upmost position, [Pr Error] will be shown every time you switch your calculator back on.
Take the three small 8-pin DIP IC's and check for their ID. The one with a completely different ID is the RAM IC. There will be two of them with closer identifiers, differing in one or two digits and having a common literal (ALPHA) chain.
If you still need advice (as Jon mentions correctly), post again with the IC's ID codes.
Hope you succeed.
Luiz (Brazil)
Edited: 15 Nov 2004, 2:40 p.m.