Nooo, strong electronic burning smell...

[delshay]

Is this probably a 3.3v memory module designed for the PC run at 5V in the Amiga? This would explain the problem. Most of the 3.3v modules do accept 5V, at least for some time, until they die from the high voltage.

3.3v simms normally have a regulator, and it is this that normally go's faulty first when memory is pushed to hard.

Overvolting memory is nothing new, even today manufacture(s) are still overvolting the chips. This is something I have been working on, custom private high performance memory module that operate within the JEDEC standard voltage.

[delshay]

Err I like to point out that some user(s) here do have 3.3v simm(s), but probably don't realize they are 3.3v simm(s).

It's the Micron MT4LC16M4H9 chips, you will find this on 64 & 128MB simms. see PDF docs.

Test here has shown their can fail in a very short time if voltage exceeds 5.5v, but at 5v no problems has been detected. A good sign there is a problem, the chip will get very hot to a point where you can't hold your finger on the chip.

ALL MODIFCATION AT YOUR OWN RISK.

[delshay]

EDO/SDRAM/DDR1/DDR2

Voltage & timings plays a very important role here across "all" types of memory modules. In a Dual Channel configuration sometimes one memory module out of the two requires 0.10v higher than the other.

Here this is considered as a fault, but is not a real fault, it just one of the two memory modules require 0.10v extra voltage to operate correctly, but this drives up overall voltage,  when clearly one memory module can operate at a lower voltage than the other. So here if one of the two memory modules requires an extra 0.10v, it is automatically rejected by default.

Here all types of high performance memory modules voltage is kept to a minimum and some will fall back into the JEDEC standard with the same or better performance (speed).      

For Simms, its the timing that is critical & voltage plays a less important role.