Whats is an MMU unit ?

[Ilwrath]

Yes, the MMU is the memory management unit, however this is usually built in the processor.  68030, vs the 68EC030.

Are you sure the socket isn't for the 68881 FPU (Floating Point Math Unit?)

[Ilwrath]

MC68030 should be a genuine Motorola "full version" '030, which means it would already have an MMU built in.  
(I can't find any references to an FE2 designation, but I'd imagine it is just a manufacturing code)

So, you should already have an MMU... Now, if the MMU is enabled by default or not on your configuration, that is another question.  A program like SysInfo or some other benchmark util should help here.

...And if you already have an FPU socket with a 68882, I'm fresh out of ideas on what that other socket would be for...  How many pins does it have?  What style socket is it?  (I haven't seen an MTec board.)

[Ilwrath]

I thought that all AOS pre 4.0 dont have Virtual mem.

True by default, however there are some (mostly ineffective) ways to add it to earlier Amigas that have MMU functions.  The MMU does not need to be (and, in fact, usually isn't) external to the processor, but maybe that socket is for adding an external MMU to a 68EC030 processor.  Your MC68030 shouldn't need one, though, as it would have MMU functions built in the chip.

The MMU features will also let you use some more advanced features in emulators.  Outside of that, though, it's of little performance gain.

[Ilwrath]

In the pic, the MMU goes in the only empty slot on the board.

Hmm...  After looking at the picture and description, I ask again, are you sure?  I think that is a PGA socket, and can be used instead of the FPGA to house a math-coprocessor (FPU).  (two different kinds of sockets, but both do the same thing, so only one needs to be in use)

Plus, as the description says, the model pictured featured an internal (on-chip) MMU.  Since your model does not have an EC030, it has a full MC68030, you should also have the internal MMU functions, already.

[Ilwrath]

the socket was put there to make sure users wern't stuck with the wrong fpu if they were buying one later on instead of with the board.  

Yep.... I tend to agree, based on what I've seen on other 68030 cards.

I think the MMU label on that socket is a mislabel. (It happens.... more often than you'd think!)