MacBook Pro Mid-2009 (5'5) RAM Upgrade Issue

i have macbook pro mid-2009 2gb of ram (1xgb). had decided upgrade 8gb after checking allowed capacity on apple support website.

ordered 2x4gb of 1066ghz ram , installed both ram sticks. machine did not boot continuous 3 beeps.

removed ram sticks , installed them 1x1gb of old stick , works fine. (so total of 5gb). have tested combination @ both slots both new 4gb ram sticks. work fine 1gb stick.

not work together. both sticks exact same model, bought them together.

there missing or doing incorrectly?

 

when boot 1 stick of 1g , 1 stick of 4g did go os verify did indeed recognize total of 5g of ram?

 

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