Question : how many vCpu to assign to SBS2008 on a ESXi 4.0 server

I will be installing SBS2008 Standard for 15 users as a VM on a HP ML350G6 with 2 Quad Core Xeon (8 vcpu) and 8 GB ram, running ESXi 4.0. Later, another VM for Terminal Server will be installed.

Of the total of 8 vCPU's that will be available, how many vCPU's should I assign to the SBS2008 VM to get the best performance possible ? I have read that assigning too many vCPU's can decrease performance. True ? And how much RAM ?

Secondly, what happens later on if I need to add 1 or 2 more vcpu's to the existing SBS2008 VM. Do I have to rebuild the SBS installation ?

Thanks.

Thanks.

Answer : how many vCpu to assign to SBS2008 on a ESXi 4.0 server

I would recommend 2 vCPU, this allows you to use multithreading but not too many vCPUs that causes performance issues.  Using too many vCPUs causes issues because all cores have to be queued up when processing takes place.  2 vCPU is nice mediun.  

The beuty of VMs is that you can move up or down if the need arises