Dual channel memory causing monitor problems

I recently decided to stick a matching pair of 512mb sticks in my computer to go with another matching pair of 512s of a different model. Both sets work fine when only used in conjunction with its matching partner but when i try to put them in together through dual channel the monitor doesn't pick up any signal from the pc but everything else boots up and loads with out any issues or alarming beeps, then when i remove a pair everything's back to normal.


any ideas what the problem could be?


I'm not sure what kind of info would be useful in trying to help solve the problem so ill try my best to provide enough information

 

Please post system specs that always helps the thought process, I am thinking you have a miss match. Have you swapped them around into different banks?