Hi I just need to know if I should have my faster ram in slot 1/2 rather than the older ones? Does this make a difference as read that the faster ones will clock down anyways to match the other 2 sticks (correct me if Im wrong)
You need to put them in the correct slots as instructed by your motherboard's manual when using 2 or more ram sticks (dual channel support), typically these are the 2nd and 4th slots furthest from your CPU. The only reason the faster RAM sticks will clock down to meet the slower ones is to keep stability within the system or you'll keep getting BLUE screens and crashes.
You are lucky that two disparate ram sticks work together.
Ram must be matched.
A motherboard needs to manage all ram exactly the same, That is why your speed will be the lower of the two.
To get faster dual channel mode the sticks must be in separate channels.
Your motherboard manual will tell you where to mount two sticks on a 4 slot motherboard.