Hi,
I know it is a noob question but I would like to ask anyway because I am not such noob.
I am scavenging a laptop with dead processor which is not worth to repair. There is a RAM (probably DDR3) and I don't have any use for it. The question is - may I use it with Arduino? I know it is more memory Arduino may hope to utilize, refreshing may take most of processor time and it needs more pins that Uno has, morover voltage level shifting will be problem. But I wonder if it is possible ... somehow.
If the RAM works as I expect I don't have to use the whole memory. I can tie some address pins to ground to reduce address space (and need for address pins) as well as read only a few (8?) data pins instead of all (64?) of them. This way I need refresh only small portion of the RAM and let the unused part to decay. But the memory expects hundreds of MHz. Will it be able to operate at Arduino's 16 MHz (or even less to be able to do all the bit banging)? Even if it works how often does it need to refresh? Is there any other problem which may cause the RAM will be unusable with Arduino?
Thanks for hints.
The fastest you can access it directly is 8 MHz with SPI.transfer.
You may need to set up some register/counters to load with an address an have an easy way to increment thru memory, and the same for data registers.
But I wonder if it is possible ... somehow.
Everything is possible. To connect a DDR3 ram to arduino would require an effort nobody will spend.. 
There were some successful attempts to connect DRAM, SDRAM to similar MCUs, but not worth of effort and the projects died.
pito:
Everything is possible.
No, perpetuum mobile is not possible.
Sure you can put the RAM into a computer and write a program that will send data from it to Arduino and back but I don't count it as "using it with Arduino". I expect maximum clock speed of anything 16MHz which may not be compatible with the RAM - I don't know.
Yes can
Check this smart Russian dude
I know about it. He is using old SIMM RAM. I doubt it means modern RAM would work as well. I was just curious, since I did not get any hint and from my brief research it looks it is impossible I postponed it to "one day".
interesting idea. /subscribing
thx man...he's smart indeed