HDD to SSD Migration: What Not to Bring With You

Cloning tools copy the mess, not just your files

A sector-level clone copies everything marked as in use — every temp file, every browser cache, every crash dump, and the old Windows.old folder you forgot about in 2022. The tool does not know junk from treasure; it knows allocated sectors, and it copies them all. Less used space also means a shorter clone run, and when you are moving from a full 1 TB drive to a 500 GB SSD, cleanup may decide whether the migration is even possible. Clean first, clone second — always in that order.

One thing you do not need to do is defragment the source drive. Fragmentation is a seek-time problem, and an SSD has no seek time: a fragmented file copied to an SSD reads just as fast as a contiguous one. The clone tool reshuffles the data anyway, and Windows runs its own TRIM pass afterwards. Hours spent defragmenting to speed up a clone are hours spent on nothing.

What to delete before you clone

Run down this list before you take the image: it is twenty minutes of work for tens of gigabytes. Everything here is either rebuildable garbage or your own history, which the new drive does not need. You will not miss any of it after deletion, apart from the last two items, where you are the only judge.

• Temp folders — %TEMP% and C:\Windows\Temp, years of installer leftovers and update debris
• Browser caches — Chrome, Edge and Firefox each keep gigabytes that rebuild on next launch
• Windows.old and update folders — often 20 to 30 GB of the previous system, which you cannot boot anyway
• Crash dumps — %LOCALAPPDATA%\CrashDumps and C:\Windows\Minidump, .dmp files that exist only for debugging
• hiberfil.sys — powercfg /h off removes a RAM-sized file if you never hibernate
• Recycle Bin and Downloads — the only two entries where you decide what is worth keeping

First boot on the SSD: two checks, then leave it alone

Open a terminal and run fsutil behavior query DisableDeleteNotify — a reply of NTFS DisableDeleteNotify = 0 means TRIM is on, which it is by default in Windows 10 and 11. TRIM is what lets the drive wipe deleted blocks in the background and keeps write speeds from sagging. Then open Optimize Drives and confirm the SSD has optimization scheduled; on an SSD that task runs a TRIM pass, not a defragmentation, whatever the button says.

Partition alignment used to silently halve SSD performance, but every current cloning tool aligns partitions correctly, and if the system booted, it booted on aligned partitions. Resist the urge to run manual defragmentation or aggressive tweaking tools on the new drive. Leave the pagefile system-managed as well — an SSD handles it fine, and Windows sizes it better than folklore does.

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