Huge memory utilisation in our production server

Hi all,

Please I would like to share with you our serious problem concerning the performance of sql production server that hosting sales Database (about 1.5 GO).

Details

• OLAP system
• Microsoft SQL Server 2008 R2 (v 10.50.1617).
• RAM 12 GO ( used 75%, avalable 3GO)
• HP Proliant DL380 G7
• DB Size 1.5
• Full Backup every 15min, and every hour and every end of the day.

Please help me to identify and diagnostic the source of the problem as soon as possible?

I am available to reply to your requests ( scripts , data....)

Thanks you in adavance

Chokri

Junior DBA