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Which is greater in RPM, 5400 or 7200?

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Short answer to : 7200 RPM is higher than 5400 RPM — it spins faster. That reduces average rotational latency (time waiting for the platter to bring the right sector under the head): roughly 4.17 ms for 7200 RPM versus 5.56 ms for 5400 RPM (average latency = one half of the time for one revolution). This is the mechanical reason 7200 drives are usually snappier for random disk access. (en.wikipedia.org)

What that feels like: for small, random reads (program startup, many small files) the RPM difference helps, but sequential throughput also depends on platter (areal) density and cache. Moving the OS and apps to an SSD usually gives a far larger real‑world speedup because SSDs have no moving parts, much lower latency and orders-of-magnitude higher random IOPS. So is right that a faster RPM helps, but the biggest leap is to an SSD for responsiveness. (en.wikipedia.org)

Why you sometimes don’t notice a difference: modern OSes keep recently used file data in RAM (the page/file cache), so re-reading hot files comes from memory at RAM speed rather than the disk. That explains cases where a slower 5400 disk still seems fast for repeat reads. To compare drives yourself, run a targeted test (CrystalDiskMark on Windows, or hdparm -Tt /dev/sdX / fio on Linux) and look at both sequential and random 4K numbers. (studylib.net)

A note on ’s caution: SSDs have different failure and retention characteristics — unexpected power loss can corrupt in‑flight writes, and unpowered data retention depends on NAND type and wear. JEDEC defines retention/endurance classes; many enterprise SSDs implement explicit power‑loss protection, while consumer drives vary. For long offline archiving choose media rated for retention (or keep multiple backups). Always back up important data regardless of drive type. (docslib.org)

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Member Avatar for djjeavons

7200 is the faster disk access. 5400 is pretty standard but if you can shell out for a faster RPM then it is very much worth it. Even better, go with an SSD.

Member Avatar for rubberman

There are issues with SSD's that most people are not aware of, such as the loss of data when the power is off for extended periods of time (recently reported information). A 7200 rpm drive will provide faster raw access speeds to data, but the overall speedup will depend upon whether you are accessing recently used data, or not. Most modern operating systems cache recently accessed disc data so that if you want to re-read that file, it will already be in memory so access is at RAM speeds - far faster than SSD's or getting it off of the spinning media once again.

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