Benchmark for Windows?

I’m quite new to the MySQL world and i wonder if there are benchmarks for Windows based MySQL-databases to identify bottlenecks and get some feeling which setting affects the performance most in a given setting.

The background:
My company used for its crm-programs for the last 10 years or so a Access based database solution and we recently switched to MySQL because of the drastically better performance with larger databases.
The problem is that our customers usually small and medium sized businesses which lack the proper it-infrastructure and the server infrastructure is very heterogeneous (from AMDs Athlons with 512 megs of RAM up to Xeons or Opterons with plenty of RAM)).

So my problem is to get good performance out of various systems and i don’t quite get the hang on which are “good” settings in a given environment.

The database structure is always about the same and the database size is depending on the customer something between lets say 200megs and 3-5 gigs.
Not really that much when i read some guys here have databases of 50 and more gigs )

So is there some way to get good performance via some rules of thumb or is there a way to benchmark the performance of Windows based databases so that i can achieve this by try&error?

I’d suggest to start from looking at example my.cnf files shipped with your mysql distribution. There should be my-small.cnf, my-huge.cnf, etc. Check them out and see what your can come up with. I think if you’ll provide 2-3 pre-defined configurations (lets say: small, medium, large) and correct guidelines when to use which of them, your customers would be happy.