as per the Microsoft Server division Weblog they were receiving a lot of feedback on the size of the package which needs to be downloaded to evaluate Windows Server 2008 R2/Windows 7 SP1 Beta as the package contains both X64 and X86 versions. due to this reason they have now published a split package which contains x86 version separate and the X64 package separate. please find below link to download the new split package
http://technet.microsoft.com/evalcenter/ff183870.aspx
