I have two of the Dell PowerEdge SC430 computers (with Pentium4-D 2.8 GHz CPU) for several years now.  They have served us well in a home-based test lab environment (I am a SQL Server Developer/DBA).  Today I upgraded one of the computer's RAM from 2-GB up to 4-GB.  I have the BIOS up to version A04 and I have the computer running Windows-7 32-bit.  The problem I have is that Windows-7 SYSTEM says only 3.25-GB of the 4-GB installed are usable.  Is there by chance a PATCH or update that can be applied so the entire 4-GB is usable?

Thank you.