My forums were crashing daily with PHP completely locked up, so I upgraded PHP to 5.1 to see if that would help. I now get CGI Timeout errors. I'm running on MySQL 4.1.14 - I'd try going up to 5 but I imagine that'll make things worse

The PHP upgrade talked about huge speed boosts which really would help out my forums, so any advice I could get on forcing this to work with the new PHP (vs yanking everything out and reinstalling the old PHP that kept crashing) would be greatly appreciated!

I have PHP5 running fine now. I am still getting timeout errors. I have about 20-30 PHP-CGI entries in my task manager at any given point of time. One of them is always pegged at 99% cpu usage, sits there for 5-6 seconds, then another item takes its place. Each one takes about 7mb of memory.

I am considering now going up to MySQL5, does anybody have any experience with that working well with this version of UBB?

Also I am investigating PHP accelerators but I can't find a free one that works with Windows/IIS. Any suggestions?

You might check out a mysql tuning tutorial posted here:

http://www.ubbdev.com/forum/showflat.php/Number/88576

May help a lot - mysql requires LOTS of ram on a busy site.