Which is faster: USB 3.0 2.5inch external, or HDD in optical drive slot?

Vero-71 · June 25, 2022

Hi,

I will be asking my question in the following order: Background, options, final question. Feel free to glance over the first two if you already know the answer.

1. Background

The company I work for has some pretty old laptops and they are now switching from internal HDD's to internal SSD's. This leaves us with extra drives which really shouldn't go to waste.

2. The two options I could think of which is relevant for the company, would be either converting the drives to external using an 2.5 external casing and connecting via a USB 3 cable, or we could use an casing which fits into the optical drive slot (we don't use cd's so the cd drive is wasted). In both cases the HDD will use a normal SATA connection which then gets converted to either USB or whatever an optical drive uses.

3. This brings me to the question: What does an optical drive use to connect to the motherboard of a laptop. Will there be a bottelneck and if so, which solution will minimize the bottelneck. Basically, is usb 3 or the connector port for optical drives faster?

Any help will be greatly appreciated.

da na · June 25, 2022

Welcome to the forums!
2.5" externals are quite slow compared to even an internal 2.5". Laptop ODDs (CD drives) use a regular SATA connector for data, but a shorter one for power. You can get adapters that go in your ODD bay to mount a HDD, you'll need one of these - they're <$10. Just search "optical bay HDD" or close to that on Amazon/Newegg/eBay, etc. Make sure you get a correct sized one, 9.5 vs 12.7 are the heights (9.5 is more common on laptops from around 2010 and newer)

Blue4130 · June 25, 2022

31 minutes ago, Vero-71 said:

Hi,

I will be asking my question in the following order: Background, options, final question. Feel free to glance over the first two if you already know the answer.

1. Background

The company I work for has some pretty old laptops and they are now switching from internal HDD's to internal SSD's. This leaves us with extra drives which really shouldn't go to waste.

2. The two options I could think of which is relevant for the company, would be either converting the drives to external using an 2.5 external casing and connecting via a USB 3 cable, or we could use an casing which fits into the optical drive slot (we don't use cd's so the cd drive is wasted). In both cases the HDD will use a normal SATA connection which then gets converted to either USB or whatever an optical drive uses.

3. This brings me to the question: What does an optical drive use to connect to the motherboard of a laptop. Will there be a bottelneck and if so, which solution will minimize the bottelneck. Basically, is usb 3 or the connector port for optical drives faster?

Any help will be greatly appreciated.

The HDD in the optical will be faster than USB since it is just a standard SATA connector. HDD and disk drives use the same connections.

Kilrah · June 25, 2022

In theory internal is faster, in practice with 2.5" HDDs you won't see any meaningful difference since the HDD is by far the limit. Internal's obviously way more convenient though.

You'll probably want to do both, have some drives in external enclosures you can give to people when they need to move stuff around and install some internally for those who need the storage even though they probably shouldn't.

Before buying tons of enclosures I'd run a SMART check on all those drives, there's probably a significant number of them that'll have pre-fail warnings and you won't want to risk continuing to use.