🚀 go-pugleaf

I have acquired a (very) old Mac, it is a Macintosh SE 
(model No M5011). It is an all in one unit with two floppies and a
hard drive. It starts to boot ok, smiley face and all, the face then
turns to a grumpy one and an error code is given (I don't have it to
hand ATM). Opening the case, I found it had 2x 1Mb 30 pin Apple
SIMMS(bank 3 & 4) and 2x 1Mb standard 30 pin (ie PC type) SIMMs (banks
1 &2). Can these old Mac's use STD 30 pin SIMMS, Can they be mixed
like this?
If I take out the STD 30 pins and leave just the Apple SIMMS the
machine stops booting at a much earlier stage, the error message is
already there as soon as the screen warms up enough to read, in fact.
Do all four banks HAVE to be fully populated for a sucessful boot?

I am not at all familiar with Macs, new or old, so any and all info
would be warmly appreciated,
Thanks......

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