lemmington_steeleWhy do SSDs have a more limited number of times data can be written to them, but RAM memory can handle loads of re-writes?
Writing to an SSD damages the SSD, however things saved to an SSD are persistent, meaning the data isn’t lost when the SSD doesn’t get any power. Writing to RAM doesn’t damage it and it is also quicker. However, data saved on RAM is not persistent, meaning that all data is lost as soon as the RAM is not connected to a power source. Also, RAM is a lot more expensive than SSD storage.
RAMs are already used to avoid writing to (or reading from) the SSD or HDD when possible, the concept is called “Caching”
Even if it's powered, RAM will lose its data on the order of a tenth of a second. RAM doesn't just require power, it requires that your computer constantly read and rewrite it - so every 64ms your computer has to read every gigabyte of RAM and write it back.
If I remember, the decay of information in RAM is slower than that. This is an old memory, but I recall I think someone on TechTV talking about how you could, if fast enough, remove a module from one machine and put it in another, and if done right, potentially get the information off it.
From what i've read it's temperature dependent, and at room temp some dram cells might take as long as 10 seconds to decay. The 64mS refresh is a super conservative call because it's really bad when random bits go missing out of memory. The decay is faster at high temperatures, but some dram controllers might actually adjust based on temperature.
fiahit is temperature dependent, if you change this refresh timing in the BIOS to the tightest possible value at a given temperature, you can easily make your PC crash by heating the RAM up a bit (for example by removing a fan)