Question HP pro 3125 MT memory issues

[Mewpman]

Hi All,
I have a RAM issue with the above tower, I have two blue and two black slots, i have 4x 4 GB DDR3 sticks bought at the same time and are all identical. i Can get the tower to boot ok with any two sticks in either pair of slots, but..... with all four fitted the fans start but will not boot. there are no bleeps from the mobo. I have cleaned the stick contacts and used an air can to clean the mobo contacts.

Any ideas please folks?

 

[rgd1101]

was the 4 stick in 1 kit?

 

[Mewpman]

Hi yes, bought from suoplier at the same time, all the same brand, speed and type.