What has lower hardware requirements? vCSA or vCenter Server for Windows?

[sofakng]

I'm using VMware/vSphere in my home development and testing environment and I was wondering which had lower hardware requirements (RAM/CPU):

vCenter Server Appliance (vCSA)

or

vCenter Server for Windows

I'm only running 1 ESXi host with about ~25 virtual machines.  I only really need the ability to use the new vSphere Web Client and create/deploy virtual machine templates.

I already have a MS SQL Server 2008 R2 server running on my network, so using the embedded database in vCSA is a bit of a waste...

The bottom line is that I'd like to use the least amount of resources possible.  I'm hoping to run the vCenter Server with 4 GB of RAM (seems OK, but does the Web Client (server) require an additional 2 GB?)

EDIT:  Also, I just realized that I use Windows Server 2008 R2 (with vCenter Server for Windows), that the OS will most likely share a lot of memory pages because I also run other W2K8 servers.  If I install vCSA then the entire OS will not be sharing any memory because I don't run SUSE/CentOS (whatever it uses) virtual machines.

[weinstein5]

As I recall the hardware requirements are comparable and they should work with 4 GB and dual vcpu -  you will get some memory savings with TPS with the installed vCenetr because of the common windows OS -

[GreatWhiteTec]

Consider the shortfalls of the vCenter appliance such as No Update Manager, No Linked-Mode, No support for VSA, No Support for Heartbeat server, etc.