Many thanks for all your replies, really useful info.

It does appear that the memory is being throttled from running the suggested queries, so we're gonna chuck some more memory...

Both the data and transaction file grow continuously, and certainly truncating the transaction log improves performance. I understand this can fragment the files, but it seems to get slower the...

Thanks for the info.

I agree, analysing using perfmon, will probably show the issues more clearly. I know that the database schema is inefficient, the main table used has 142 columns!,...