Some suggestions, all of which may help and none of which may help:
First down load this screen shot and make sure that when you go into SQL Server Configuration Manager (there are other things such as studio that sound the same), you see something like the screen shot listed here:
http://www.box.net/shared/641s27xf1aOn your clients, you should NOT have SQL server in any capacity (except possibly SQL writer) on your computer. You can check in three places:
1. Start menu -- you would see it there
2. Add/Remove Programs -- you would see it there
3. Finally your services (which if you don't know what or where they are, you should. Many ways to get there but easiest way is to go to "Run" on your Start menu and type in "services.msc" without the quotes and hit enter. There should be no service with SQL. Look under SQL and under MSSQL, although SQL writer may be in there.
(Just for a learning experience, go to the "main computer" and all three of these places should show the SQL servers.)
RAM should look like this:
XP = at least 1GB
Vista or Win7 MUST have at least two
Your main computer should have 4GBs (remember with 32 bit -- which I know you have, the computer only "sees 3.2GBs -- with 64 bit it can see up to 64 bit. You can see where we are headed).
Remember or know that 2 x 2GBs is better than 4 x 1GB -- trust me.
Also, while my server will run for weeks without a reboot, SQL just eats up memory and sometimes leads to memory leaks, although debatable. For fun, check Task Manager, Performance Tab, and look at Physical Memory on top right of the bottom grey portion. The total should reflect what you have in the machine while the available is what you have, well, available.
If you look at Processes Tab, you will see that SQL Server takes up most of your RAM. Some would argue that it doesn't.
I should have installed SBS 2008 as I could have put in 3,16, 32 or 64 of RAM. Then it wouldn't have been an issue.
AS Wendell says, move to a GB switch, Netgear or Linksys, make sure you have at least Cat5e -- if you need to upgrade, to go Cat6 -- one day there will be fiberoptics. Each computer will need a GB network card, which will run about $15 to $50 depending on name brand or not. Make sure if you have a card that your motherboard doesn't already have an embedded GB Ethernet card (NIC).
While 100MB/s vs 1GB/s probably won't make that much difference with the amount of data coming from the SQL databases, it will help on larger file transfers.
As far as the above, add memory to "main computer" first. You can go to your computer's manufacturer's site and look up your config or look directly at the memory or go to
www.lavalys.com and download Everest Ultimate Edition. The trial version is helpful but, as with most trials, is a tease, and will find your RAM but will not identify it for you.
The Corporate Edition will work with databases and networking. Very helpful software. Other advantages of Everest (Lavalys) is it will print out a complete and thorough configuration of your system so you can send it to a knowledgeable computer person, e.g. someone on the boards other than I if you need help.
Finally and probably the best method for memory detection and compatibility is to go to one of the leading manufacturers of memory such as Kingston or Crucial. I like crucial at
www.crucial.com. They have all sorts of self help tools and scanners to identify your memory or you can use their live chat.
As Benjamin suggested using the Advanced tools on the utilities section, you can check the difference between the main computer and your network computer. If one is 1 second, and the others are 5 seconds, there is a big network problem. But, this may not be helpful if you don't have your "main computer" at optimal conditions, e.g. enough RAM, CPU, etc.
