Thanks for your enquiry
If you are looking to upgrade your RAM, or if you have already bought some RAM and it is not working & you suspect you may have purchased the wrong items
Please can you tell us the full make & model number of your system, PC, Laptop or motherboard ?
If you dont know this you may be able to get the information by typing msinfo32 in the Run or in the Search box. & Click on System Information,
and sending us a screenshot of what you see on the main page
We may be able to see what your system is from that info
Alternatively if you remove one of the sticks of memory you have installed at present and send us photos of this RAM including the stickers on the RAM we can try to ID your upgrade that way.
However we wont be able to advise you on your systems max sizes or capacity without model numbers for your PC.