The question is broad so the answer is also they use sodimm,which are smaller modules in a 200 or 204 pin attachment....the newest would use DDR3,older DDR2 or DDR.The best way to check what you have is to find out the specs of your motherboard,with that information you could buy the right type and amount the motherboard could handle.....side note if your running Xp it can only handle 4 gig's of ram if your board supports that amount
Laptops use SODIMM ram or SDRAM
The RAM is use in laptops are SD-RAM
Most laptops allow you to replace the ram chips with better ones. There are videos on youtube of people replacing ram in laptops, but posting links on this site is not permitted. The exact action depends on laptop and some laptops do not allow that (ram welded to motherboard, all new apple laptops do that for example)
upgrade the ram. use crucial advisor to find the right kind
RAM (also know Main memory - dynamic ram) which is inside the CPU is used fir holding any data currently in use by the processor.Registers (which are a form of Static RAM) which are in the processor are used forHolding data that is being transferred to or from memory(RAM)Holding the address of the location in memory which the processor is accessing to read data from or write data to.Holds instructionsthat are being executed.
DIMM is also called a RAM stick, its a kind of circuit board used for our personal computers and laptops.
I agree with Rtrahan that most laptops have two RAM slots (though I have seen some that have three or even four slots but those are usually gaming laptops rather than run-of-the-mill machines). However, he is incorrect that both slots have to be used. Instead, many laptops actually come with a single RAM stick and leave the additional slot open for the user to add more RAM if/when he decides to do so. The only concern is to make sure that the speed of the RAM that is added later is the same as what is already in there. If the added RAM is faster, then it will be slowed down by the original stick of RAM and you have just wasted your money on speed that you can't use. If you, instead, get slower RAM that what is already installed, then you will be bottlenecking your machine because now the original RAM will have to slow down for the new RAM, thus degrading performance.
A 1998 Ram uses R134a.
Most notebooks use a SATA Hard Disk Drive for storage. Typical notebook hard disk size is 250 to 500 GB. For RAM, practically all personal computers use flash (solid-state) memory. Typical notebook RAM is 2 to 4 GB.
cdrome
Depending on your motherboard it is most likely because most motherboards can only use one type of ram at a time. So you can only use ddr with more ddr to see more than one stick of ram.
In my experience I have found that Dells have a higher capacity for memory. While there is no "perfect" desktop laptops, the best choice is finding what works best for your needs. If you need additional memory you can easily get flash drives which are inexpensive to use and free up our computre to run faster.
mobile cellphones, tablets, notebook and desktop.