Typical cheap 120Gb SSD internals.
It is already budget controller, but still require for proper speed (writing especially) to have all 4 channels working.
Yet most manufacturers buy larger capacity NAND chips and just use one.
Hence the writing speed that can even match horrible one of QLC SSDs.
Hence usually older 120Gb or 240/256Gb SSDs are usually much faster compared to modern ones, even with both have 3D TLC memory.
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