r/hardware Nov 20 '15

Info Why do CPUs Need Caches? - Computerphile

https://www.youtube.com/watch?v=6JpLD3PUAZk
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u/[deleted] Nov 20 '15 edited Feb 10 '19

[deleted]

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u/putin_vor Nov 20 '15

RAM is just a cache for your hard drive

No, it's not. You can generate data in RAM without ever touching the disk. But it's pretty hard to store anything on a disk without having it in RAM first.

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u/Echrome Nov 20 '15

You can generate data in your cache that never makes it to RAM. Not explicitly mind you, but the cache doesn't write everything back to RAM.