Sql server 2008 Max Ram

[BLAUPUNKT91]

Hey guys, i have a big problem with my Root Server

Server Info:
System: Windows Server 2008 R2
Processor: 2 x Intel Xeon - E5504
Perfomance: 2 x 4 x 2,0 GHz
RAM: 32 GB DDR3-RAM
Harddrive: 4 x 1.000 GB SATA II
Network: 1.000 MBi
SQL: Sql Server 2008

Now my Problem:
I have 300 Players on my Server and he have big lags and delays when he skill or Change his Weapons.

I Think it is the Database.. My Database need only 1,2GB Ram, it this normaly?

When not, have the SQL Server settings with max ram?
I have ask google but i can´t find something.

Have anyone the same problem fixed?
Poeple who have Tips get a big Thanks
People who have the solution i get him freely a PSC :P

Thanks