The short answer to this question is no, you cannot have three slots of RAM. However, the long answer is a bit more complex.
RAM is essentially a storage device for your computer that can hold certain pieces of data temporarily so that your computer can use them again. RAM is located directly on your computer’s motherboard and can be upgraded or replaced.
One common type of RAM is called DDR3 or dual-channel memory. This type of RAM can support up to three slots, but in reality only two are usable at any given time because the third slot is used for backup or configuration purposes.
So, in theory, you could have two slots of DDR3 memory and one slot of DDR2 memory, but in reality you would only be able to use one slot of each type of memory.
Another type of RAM is called DIMM (dual inline memory module). This type of RAM doesn’t have a physical slot on your motherboard and can instead be installed in a PCI Express slot or an expansion card.
So, theoretically, you could have four slots of DIMM memory, but in reality you would only be able to use three slots because the fourth slot is used for backup or configuration purposes.