I use that setup too : 1 server with iis and 1 with SQL server (2000)
So when site 1 times out the other which uses the same sql server works fine? Thats a real mystery. This makes me think there's something wrong at iis side.
Can you give me the exact error messages that iis returns? A time out can also occur on IIS (default 20 sec) and not only on sql server. The screenshot dont tell a lot, they only confirm what you told me. We must be 100% sure that the problem lies with sql server or with one of the subsytems (I/0,memory,...)
I am trying to help but its very difficult if i dont have access to the server. Can you move the sql server to antother machine, maybe your desktop? If the problem doesn't accore on this setup I think its machine related. I had my share of problem with bad hardware servers and when i switched to one i had more confidence in they went away.
When I see sql server answer slowly I first start up profiler. This is a tool thats installed together with sql server and shows you all the queries that SQL server handles. Watch for the duration of the query. This is not the same as CPU. I note this because CPUT is at max 10%.
Is it the machine or the service you restart When you rebooting the IIS server?
when the server stopped responding, select * from master.dbo.sysprocesses to see what happening there. My guess is that some process are doing extensive I/O to harddisk. Or use PROFILER is a good idea to try.
There is a time-out problem reported when SQL Server is expanding it's data-files. I don't know if there is many data added using the website, but SQL Server is know to give a time-out when increasing/decreasing the size of the datafile takes too much time... You can control this option by using smaller values for the Auto Grow / Auto shrink options...