i am think about changing my current website from a LAMP architecture (lynix/apache/mysql/php) to a windows/asp.net/dnn/sql server architecture. i have found some information online about the limitations of the various versions of sql server (express,workgroup,standard) but i have not been able to find out the limitations of the LAMP model. the current server has 16gb ramand uses a raid 5. i would think that would be wayyyyyy overkill for a site that has about 700 hits PER DAY  - and yet.....every afternoon the site comes to a C-R-A-W-L. i find this very surprising.

can anyone give some advice on why it would or would not be better (performance/cost wise) to switch to a windows/.net/dnn/sql server model? and does anyone know the limitations of the LAMP model?

if my site went from several hundred to several thousand hits per day.......which version of sql server would you recommend? 

Ideally you would use the full version of SQL Server, but I have had a dozen or so sites (a mixture of ASP.NET and classic ASP) on a dedicated Windows Web Edition server with Sql Server Express and 512MB or RAM running happily.  Altogether, they probably served up anything up to 20,000 page requests a day.

As to why your current setup crawls, no one can answer without knowing what else the box is repsonsible for, what your code is like etc etc.

I wouldn't use DNN, by the way.....

 just curious....why not use DNN? - i'm trying to give my client a content management system coupled with dotnetstorefront for dnn for ecommerce.

btw......the current php/mysql system has 16gb of ram on a raid5 to serve 2500 hits a day. seem like overkill??? 

I wouldn't use DNN for one simple reason - they've written books on how to configure and use it.  Any CMS that needs books written for it will not be straightforward.  Just a personal opinion

Your current set up is more than adequate for the requirement.  So it must be something to do with how it's configured, or how your apps are set up, or who knows?  I have no experience of LAMP.  That's a question for a more appropriate forum.