SSHD Cache vs HDD Cache

[1405]

I'm a little confused between the cache used on a SSHD compared to the one on a regular HDD. The common 7200 RPM 1TB HDD has a 64MB cache. The Seagate SSHD I see only has a 64GB cache as well. Is the only difference that the SSHD's cache is persistent (doesn't lose memory when shut off)?

 

[USAFRet]

I'm a little confused between the cache used on a SSHD compared to the one on a regular HDD. The common 7200 RPM 1TB HDD has a 64MB cache. The Seagate SSHD I see only has a 64GB cache as well. Is the only difference that the SSHD's cache is persistent (doesn't lose memory when shut off)?

You're a bit off with your values. SSHD's don't have a 64GB cache. (Unless they've upped that a LOT lately).
It may have a 64MB 'cache', simply as part of the regular spinning platter. It also has a small SSD portion, 8 or 16GB.

The cache on a regular drive is a temp landing space. A buffer before it goes in our out of the platters.

The SSHD is a regular HDD, with a small SSD space. 8 or 16GB. Many times larger.
The drive firmware learns what blocks of data are used most often, and those end up in the 8 or 16GB SSD space.
Its like having a tiny SSD in your system.

If you have only one drive, an SSHD may be beneficial.
Otherwise, a combination of a traditional HDD and a real SSD (250GB or so) is better.

 

[IInuyasha74]

I think WD actually made one with a 64GB cache, but most are still just 8GB.

But to explain a little more, an HDD's cache is like a small amount of RAM dedicated to the HDD. It's primary purpose it to accelerate file navigation.

An SSHD is essentially an HDD with a small SSD inside. It will also have a cache file, as the SSD doesn't perform the functions of the cache. Frequently accessed files on the HDD portion of the SSHD will be duplicated on the SSD portion of the drive to significantly boost load times. This is most noticeable when the PC boots, and the time required to boot the PC is often reduced quite a bit over just an HDD.

Like USAFRet said though, an SSHD is beneficial if you have just one drive. Otherwise, an SSD for your C: Drive is usually best, with an HDD for extra storage.

 

[1405]

OK, thanks guys. Now I get it. And yes USAFRet, I mis-typed and meant 64GB. The 64GB referred only to the normal cache on HDDs. OK. Good to know.

So, since regular 1TB HDD's are going for around $50 now, the $74 Seagate SSHD is like paying $23 extra for the small 8GB SSD. Yes?

 

[USAFRet]

OK, thanks guys. Now I get it. And yes USAFRet, I mis-typed and meant 64GB. The 64GB referred only to the normal cache on HDDs. OK. Good to know.

So, since regular 1TB HDD's are going for around $50 now, the $74 Seagate SSHD is like paying $23 extra for the small 8GB SSD. Yes?

Yes, but you don't get to choose what data ends up on the 8GB SSD portion.
The drive does.

(and you meant 64MB, not GB... )