Exchange Server

[#1]

Just a thought, if you're building from scratch, you might want to consider the SBS 2003 product line.
Dabs are doing a previously opened OEM Standard version (I think it doesn't include SQL server - but you might want to check on that first) for around £200 mark.
Or if you have any IT connections, try a Microsoft Action Pack subscription, approx £200 pa gets the latest MS products delivered to you.

Also, if you will be building up lots of e-mails in Exchange, when it comes to shutdown time, the server may take longer to actually shutdown than your currently spec'd UPS will have battery power for (I know it says 45 mins - but real world experience has it that these are vastly overrated figures), you might want to consider a higher powered UPS, say 1000VA.
HTH

[#2]

Agree with parent poster.
If you are going to be running Virtual Machines, I would spec for as much memory as you can throw at it though.
We currently have two Dell PowerEdge 2950 servers, running with 8GB memory each and twin E5320 Xeon processors in them.  These servers are running CentOS 5, and VMWare Server 1.0.3 (and not much else apart from sshd ;))
Each server is a host to several virtual machines which handle our main Databases (2 x MySQL master/slave/master), Email (postfix/dovecot/squirrelmail/Spamassassin/ClamAV), Domain Controller (SBS 2003) and remote access host machines (running XP Corporate) quite happily.
We didn't go the ESX server route - it was too expensive tbh.
The beauty of going the VM route for us is the ease at which we can maintain and upgrade the underlying hardware.  In the event of a fault on one physical machine, we can very quickly provision the affected "virtual" servers on the other server (albeit with a loss of performance - but a slow server is better than a powered-off server ;)) so that we can diagnose the fault and repair it. 
In addition, in the future we can simply add more hardware to the array, and balance out the VM's across the new hardware very quickly.
Or, we can buy in spangly new hardware, and over a weekends maintenance window simply transfer the existing VM's from the old to the new server and turn them back on.
Virtualisation is a developing market, (look at VMWare's IPO yesterday!) however it is absolutely brilliant from a technical standpoint to allow you to compartmentalise your servers without having to purchase large numbers of additional servers. 
Want a testbed?  simply clone our existing preinstalled XP-Corp image, and power it on (takes about 30 seconds).  When you're done, simply delete it.
Backups are handled by snapshotting the running Virtual machines and backing up the snapshot to disk.
If you're an IT Pro, I would seriously recommend investigating VMWare Server - you can download and use it for free in certain circumstances and it *is* going to be the "Next Big Thing"
Barry

[#3]

Quote from: James_H

You can create extra virtual machines for other OS's too, so you can create one to run as a gaming server, and only switch that on when you want.

Actually, we do this for our remote workers.
We were considering implementing Terminal Server, but it's pretty much overkill for the number of external guys we have.
So, we created a set of XP images which are set up for each user, and joined to the domain etc.
When the user VPN's in, a command is sent to the VMWare server to un-suspend their particular Virtual Machine.  They then use VNC or RDP to connect to their machine.  When they're finished, they simply disconnect VNC or RDP, then disconnect the VPN session.  The host then sends a 'suspend' event to the virtual machine.
That means that the VM is only running when it's needed.
A similar method could work for a game server - or you could just "choose" to start and suspend it.  However, I'd probably set up some sort of tunnelling proxy so the VM is started when a connection to it is required, (the un-suspend time is of the order of 0.5-1 second) and the VM is paused when no connections are live. 
Not necessary, but I like tinkering
Barry

[#4]

Quote from: zubel

If you are going to be running Virtual Machines, I would spec for as much memory as you can throw at it though.

I will second that.
For details of my VM set up;
http://www.chillypenguin.org/vmware/vmware.htm
Chilly

[#5]

Yep, they look good to me for what you want.
Its all Memory, memory, memory where VM's are concerned.
B.

[#6]

I think what you are trying to do is not worth the effort. No one would run a Ad server, exchange and SQl on the same box as SQl needs loads of power on its own.
As most of the stuff is beta anyway what you learn may be wrong and full of bugs. To gain employment you need to have used these things in a commercial enviorment.
Setting up SQl  and running a little database doesnt compare to running it at work when 30,000 users are using it and it mission critical and companies would be looking for someone who could set it up for that situation and recover it if it died. They would be looking for clustering DTS etc.
The same is true of exchange etc.
Decided what you want to do using SQl is a full time DBA job on £40,000 a year very few people mess with all 3 things other than adding users and simple stuff.

[#7]

If you want to save your self some money Exchange etc will run on fairly low spec PC's as long as you have plenty of disk space and RAM. Unless it is being run with alot of user activity  you do not need anything too powerfull. I did have Exchange 2003 running as test system for a while on an old HP PC and it worked fine. The same is true of SQL2005 etc.

[#8]

I am currently running SBS2003 in VMWARE 6 on a 2GHz XP2400 with 1.5GB ram and SATA drive, giving the VM 768MB and 20GB disk and it runs fine. So your spec should be fine.

[#9]

Sorry to hear about your Dabs experience..
We actually use them and have a business account so can actually speak to an Account Manager who can generally sway the delivery company to deliver as necessary.
As to APC - there is an APC daemon called 'apcupsd'  which I run on our Dell Poweredge 2950 system, connecting to APC UPS devices which works fabulously
apcupsd supports serial, and usb UPS connections and afaik supports the entire APC range.
http://www.apcupsd.org/ should give you a good starting point!
Barry

[#10]

Also NUT http://www.networkupstools.org/ may be able to work with the APC
Chilly

[#11]

No problems Peter - I spend a lot of time hunting down exotic (and not so exotic) Linux ports of things to help with my employ - any knowledge I can impart I offer freely.
Barry