I have a motherboard from dell inspirion c521 little bit old by now but anyways as soon
AS soon as i try to do dual channel with the same memory it shuts off and as soon as i put the memory into 2 different slots it start up normally and reads 1gb ram but not as dual channel of course all the ram sticks worked i tested them out i have 3 ram sticks and all at 512mb but idk why it shuts off i i place it in dual i tried it all already and found out it just wont read dual channel and if it does it might shut off can this be due to the psu
The PC ram will run single or dual channel mode, but if you mix two difference brand ram, then you will have the uncompatible situation like you case. So you only can do, which is to try the combination to see which ram works with each other. Or buy the new set of ram.