I just replaced my old HD from a late-2009 iMac with a new Samsung SSD 850 EVO 1TB.
It was installed by an official Apple repair store but I am worried because it seems slower than my new macboook pro (also with SSD)
I tested with Blackmagic Disk Test and it:
- Writes 253 MB/s
- Reads 268 Mb/s
Official specs say it should:
- Write 520 MB/s
- Read 500 Mb/s
And it seems from reviews they get numbers close to official ones.
I checked my SATA Chipset in the iMac and it says: "Link Speed: 3 Gigabit".
Does this mean that 3000 Mb/s (Megabits) are 375 MB/s (Megabytes) and it cannot transfer faster (even though the SSD is faster)?
Best Answer
I would make sure that TRIM is enabled. Without TRIM, SSDs will run slower. I use Trim Enabler to turn on TRIM on my Samsung SSDs.
https://www.cindori.org/software/trimenabler/
Nowadays it can enable TRIM without disabling kext signing.
https://www.cindori.org/safely-enable-trim-on-yosemite-and-el-capitan/