Of course, if the server has less than 4Gb of RAM, then actually *using* the full 4Gb of virtual address space requires you to swap memory to disk, and that kills performance something chronic.
Same for 64 bit, with it's 16 TB of VAS (limited to 16TB from the many exabytes actually addressable)
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)SQL In The Wild
: Discussions on DB performance with occasional diversions into recoverability
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