External USB Drive Sometimes Not Detected at Boot

I have a 2TB external Seagate Expansion USB hard drive connected permanently via USB 3.0 to my desktop PC mainly used for scheduled Reflect backups (I also back up to another USB drive stored elsewhere). The PC is running Windows 10 Pro 21H1 build 19043.1052.

Sometimes at boot the drive is not connected but does appear after a restart. Chkdsk and the SeaTools disk utility does not find any errors with the drive. Have you any ideas what is causing this?

I might replace the drive anyway with a high capacity internal drive for scheduled backups which is likely to be faster and more reliable. The choice is between a Seagate BarraCuda or WD Blue internal drive. Which is better for reliability?

Guessing- is Fast Startup on or off? - noted you probably have a SSD as system disk.

Reliability- personally it's always seemed to me Hitachi or Toshiba are more reliable (HDDs) - SSDs - not looked.

dalchina said:

Guessing- is Fast Startup on or off? - noted you probably have a SSD as system disk.

Reliability- personally it's always seemed to me Hitachi or Toshiba are more reliable (HDDs) - SSDs - not looked.

Fast start up is off and system drive is a SSD

One idea as to the why, could be the sequence in loading of drivers for the USB ports is the issue, OS gets loaded too quickly. Saw the same issue years ago where an HDD didn't get recognized during boot and had to change the displaying of the BIOS P.O.S.T. [Power On Self Test] to delay long enough] for the HDD to get recognized properly and load the boot process [usually 10 seconds was suitable].

dalchina said:

Guessing- is Fast Startup on or off? - noted you probably have a SSD as system diskReliability- personally it's always seemed to me Hitachi or Toshiba are more reliable (HDDs) - SSDs - not looked.

Your Toshiba suggestion is an interesting idea. I noticed the higher capacity 3TB+ Seagate Barracuda and WD Blue drives spin at only 5400rpm whereas this 3TB Toshiba drive spins at 7200rpm but has a small cache of 64MB Toshiba P300 3 TB 7200RPM 3.5 Inch SATA HDD: Amazon.co.uk: Computers & Accessories

The Seagate and WD drives have a 256 MB cache. Is it best to have a higher 7200rpm spin speed with the small cache or a slower 5400rpm spin speed with the larger cache? This drive will only be used for backups.

Cache should be irrelevant for backups. Reliabilty wins over speed. USB3 vs USB2 is a more significant factor assuming it's going to be USB connected - transfer rate for larger files or continuous transfer.

Also depends what sort of backups you're doing. E.g. outright transfer speed for, say, disk imaging where lots of data is both read and written if performing incremental or differential imaging.

If synching for file backup, varies depending on number and size of files changing in a given period.

So there's no one answer.. but I doubt you'd benefit from 7200rpm.

dalchina said:

Cache should be irrelevant for backups. Reliabilty wins over speed. USB3 vs USB2 is a more significant factor assuming it's going to be USB connected - transfer rate for larger files or continuous transfer.

Also depends what sort of backups you're doing. E.g. outright transfer speed for, say, disk imaging where lots of data is both read and written if performing incremental or differential imaging.

If synching for file backup, varies depending on number and size of files changing in a given period.

So there's no one answer.. but I doubt you'd benefit from 7200rpm.

To be clear, I'm thinking of replacing my external USB backup drive which might be dodgy with an internal drive which should be faster and cheaper. I'm using scheduled Reflect v8 backups. I'll also have other Reflect backups on a removable drive not usually connected to the PC.

Update - I decided to buy a 4TB CMR hard drive for backups and selected a WD Blue version WD40EZRZ. I discovered many large drive have SMR recording. Toshiba drives have much worse reliability according to Amazon feedback although were slightly cheaper.