Difference between USB powered external drives and mains powered

Skalaberg · 25 Mar 2019 at 00:23

Looking to buy a 4TB external drive as my ageing (about 8 years old) 1TB internal sounds like its about to fail. The speeds between the usb powered and mains powered drives look about the same... what am I missing here, why would I go for the mains powered ones when the USB appear smaller and dont need mains power?

https://www.overclockers.co.uk/seag...rnal-desktop-drive-steb4000200-hd-3au-se.html

https://www.overclockers.co.uk/maxt...ernal-hard-drive-hx-m401tcb-gm-hd-182-md.html

gEd · 25 Mar 2019 at 01:08

Typically the difference is that the larger mains powered HD will run at 7200prm compared to 5400rpm on the laptop sized disk and will therefore generally be faster. However both companies seem a bit coy on the precise specs of their disk beyond saying "5GBs USB3 speed" which is just the speed of the interface and not of the disk itself. The maxtor has an extra 1 year warranty and while is likely a bit slower that the seagate drive, it will be a more convenient drive for backup purposes.

chrcoluk · 25 Mar 2019 at 01:30

Any 2.5 inch drive I have ever used can be powered by usb. The difference can be as simple as just the casing on these 2 products. One been designed to accept usb power, the other not.

I dont know if 3.5 inch drives can be powered by usb, I never tried it.

Skalaberg · 25 Mar 2019 at 19:16

Thanks for the advice guys. Managed to pick up a 5TB Seagate USB at a reasonable price.

Skalaberg · 27 Mar 2019 at 20:55

For whats its worth the drive arrived. I have copy and pasted the contents of the old 1TB over and disconnected it. Renamed the external and changed the drive letter to match the old drive and it works like a charm. i have some Steam games on it along with uplay ones and origin which all continue to work as if I'd never changed anything. Speeds on it are around 136mb/s. Very happy.