has the requirements. It's the same location where you downloaded the install files.
Memory
3 GB, DDR2. (min) 4 GB or more, DDR2 (recommended)
Disk
18GB free SATA (min)
20 GB free or more. 10,000 rpm SCSI (recommended)
Software
Operating System Windows Server 2008 R2 x64
Latest updates of SQL Server 2005 or SQL Server 2008
In evaluation environment, you can do the following:
■ Use an Express Edition
■ Install SQL on either the 7.1 server or another computer
SQL
Internet Explorer 7.0 or above
Microsoft .NET 3.5 SP1 or above
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So, SQL 2008 R2 is not explictly unsupported, but it's not listed as supported either.