HGST He8 8TB SAS vs DC HC510 8TB SAS

[SubnetMask]

Does anyone have any info on what the difference is between these drives? Near as I can tell, the only real functional difference is one (He8) has 128MB cache and the other (HC510) has 256MB - other than that, they seem to be pretty much identical. I currently have four He8 HUH728080AL5200 drives and need to get four more, and while I'd like to keep them all the same, I can get the HC510 HUH721008AL5200 for a better price with the same warranty. Would the different cache sizes have any impact on FreeNAS in a 8 drive RAIDZ2 volume?

 

[jgreco]

Assuming the cache is the primary difference, there would be a modest difference at best, assuming you're using RAIDZ2 for what it's designed for. Cache favors seek-heavy environments, and RAIDZ is best at sequential data storage.

 

[Chris Moore]

He8 HUH728080AL5200

https://documents.westerndigital.co...astar-sas-series/data-sheet-ultrastar-he8.pdf

HC510 HUH721008AL5200

https://documents.westerndigital.co...c500-series/data-sheet-ultrastar-dc-hc510.pdf

Data sheet says the sustained transfer rating is higher on the newer model. Just looking at the photos, there is a mechanical difference in the drives.

 

[Johnnie Black]

HC510 was formelly the He10, so it uses platters with higher density that translates to faster sustained transfer rates, but there won't be any problem using it together with the the older model.

 

[SubnetMask]

Thansk Johnnie - that's the kind of info I was looking for. On the surface at a high level, the main difference that stood out was the cache difference. Since the HC510 was originally the He10, that's probably the better drive to go with anyway.