i also have an issue - when putting one of these simms I got himem error, why?

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hi, when I removed them from my old computers 25years ago for sure they were.

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try a different cpu if you have one, or at least remove and reinstall. I have had alot of cache and some ram errors on a faulty cpu socket before, reseating cpus would give different results which helped diagnose a socket problem

only these from 4th picture have the issue... other are ok.

the last number on the chips are the speed.
So you have a mix of 60 and 70ns Ram, faster is better so 60 are the more desirable.
The Topless (hehe) simply has a sticker telling you its 60ns

So use that first, but if that doesn't give you enough (say 4MB, I wouldn't have a problem adding a 70ns simm