HDD 16mb cache vs 32mb cache

[Matt Rushmore]

I've looked through a bunch of threads on here and while I have found a couple that say 32mb drives give better recording performance, I can't find any that say how much or how necessary it is.

Why I ask:
I have two 500gb Caviar Blue 16mb cache 6.0 gb/s drives (one system, one recording). I am going to buy a third drive for samples. The easiest drive for me to get locally is another Blue (3.0gb/s) with a 16mb cache.

But, after reading the duc and the web I am curious if I should go through the trouble of ordering a 32mb cache drive (either a blue or black) and make that my recording drive.

Which poses another question since my motherboard only has two 6gb/s sata ports, could I put a 6gb/s drive on a sataII port? Or would it cause issues? Thats what I'd kinda have to do if my new drive was to be my new recording drive.

OR, maybe get a 3.0 gb/s Caviar Black 32mb cache recording drive? And leave my 16mb drive on my 6.0gb/s port even if its used for samples?

The choices make my head spin. haha

Thanks for any opinions.

[jntracks]

none of those drives can transfer data even at 3gb/s so it doesn't matter if you put any of those drives on sata 2 or sata 3 ports. they're all backwards compatible so they'll run as fast as the drive can on any of those ports.

32mb cache will let the drive perform better. the black is the best record drive, but even the caviar black won't transfer as fast as the sata 2 port can handle so it doesn't matter which ports you use.

there are a few factors that go into the transfer speed of HDD.
RPM affects long file transfers, sustained speed. 7200 is good, more is better, but is more expensive and noisy/power hungry. 7200 is good for a record drive, you'll get lots of tracks out of that.

cache size. this is the size of the "ram" memory that's on the drive controller. so this is the size of each chunk of data that gets passed to the system. the drive reads and fills this cache, transfers that to the sata port, then reads the next chunk, and so on... more is better, obviously. 16 is good enough to record with but as prices come down you'll find better and faster as you upgrate.

last is areal density. this is how tightly packed the data is on the platter. the larger the drive capacity, the more tight the data is packed. so that means a single spin of the platter contains more data that can be loaded into cache. so this one is a factory, but it relies on the other two to make a difference. the final effect is that a 2Tb 7200 rpm drive with a 64mb cache can transfer data at speeds that start to come close to the capacity of sata 2.

if you want a drive that will saturate sata2 or even take advantage of sata3 (6gb/s) you are looking at solid state drives. and obviously those capacities make them no good for recording. hahaha!

[Matt Rushmore]

Very detailed and good response. Much appreciated.

When would I notice a difference between 16mb and 32mb? After a certain number of tracks? Randomly when the cache got full? Only if I had a bunch of errors or something that would use up the cache?

Your "more is better...obviously" part made me think that thats not what I should have assumed when I bought my 6gb/s drives after what you said about them.
So, I guess it's a good thing I'm digging deeper on the cache part because more is sometimes not better, just more expensive (if youre talking about 6gb/s hard drives anyway).


Thanks again.

[Dism]

Originally Posted by Matt Rushmore

Very detailed and good response. Much appreciated.

When would I notice a difference between 16mb and 32mb? After a certain number of tracks? Randomly when the cache got full? Only if I had a bunch of errors or something that would use up the cache?

So, you're saying 6gb/s drives are all just a marketing ploy to get $10 more per drive out of you? Or did I read that wrong? Google here I come! Darn marketers!
lol, that doesn't surprise me.

Thanks again.

You most likely won't notice much of a difference between 16 and 32. It really comes down to platter size. On a 320-500GB drive, you won't notice, but on 1TB or more you may.

The cache doesn't get "full" in the way that RAM does. The cache fills and dumps on a cycle, it doesn't fill up and then drag. It fills until it has to dump, and then refills and so on.

[Matt Rushmore]

Thanks a lot Dism.

I'm gonna get the Caviar Blue 16mb one then since its 500gb, local and cheap. :)

[Benoni]

why stop at 32MB cache, the 64MB cache drives are about the same price now. They are SATA III as well (6Gb/sec)

Shop at newegg.com, they usually have free 3 day shipping.

http://www.newegg.com/Product/Produc...82E16822136794

http://www.newegg.com/Product/Produc...82E16822136544

http://www.newegg.com/Product/Produc...82E16822136533

http://www.newegg.com/Product/Produc...82E16822136792

be sure to have a backup drive.

Newegg has a good deal on Re-certified Mybook Home external drives with the Tri interface (USB, Firewire, and eSata)
I bought a recert. mybook about 4 years ago and its still going strong, so i just bought another one.

http://www.newegg.com/Product/Produc...82E16822136528

if you dont trust a recert. then buy another Black or Blue Caviar and put it in an external case like this:
http://www.newegg.com/Product/Produc...82E16817173042

these even come with an eSata bracket in case your PC does not have a eSata port. I have 2 of these and they are nice. The fan is quiet, and can be turned off, if its still too loud for you.


And you should have a dock as well, these come in handy when you have several drives with different backups sitting on a shelf.

http://www.newegg.com/Product/Produc...82E16817182197

and if you dont already have it, get acronis true image home 2011. I suggest getting the Plus pack add on.
http://www.acronis.com/homecomputing...cts/trueimage/

[jntracks]

get the biggest capacity with the biggest cache you can. (or is worth it to you)

DO NOT pay more for sata 3 (6gb/s) on a spinning disc drive since they can't even transfer as fast as sata 2. no need for the faster interface if the device isn't even saturating the old interface. waste of money.

[Eric Seaberg]

We had 4-WD Black Caviar SATA 3 drives in our HP XW8600 and had bizarre problems. The same weekend I decided to pull the drives, we got a notice from HP that their motherboard would not support SATA 3 (32MB cache @ 6Mb per sec) drives. We purchased SATA 2 drives (16MB cache @ 3Mb/sec) and all has been happy.

IMHO, unless you KNOW your system can support them, don't waste the money.

[Matt Rushmore]

Thanks guys. Way cool of all of you.

I only wasted about $10 per drive for the two I got at 6.0 gb/s. Cheap lesson. :)

[Benoni]

Originally Posted by jntracks

no need for the faster interface if the device isn't even saturating the old interface. waste of money.

Well thats not really the point. Whether it is "saturated" or not, is a moot point. The point is the SATA III interface will give better performance over SATA II, though slight, it is still faster. Every head to head test i've seen between a SATA II (aka SATA300, aka SATA 3.0Gb/sec) and a SATA III (aka SATA600, aka SATA 6Gb/sec) drive, the SATA III always comes out on top, no matter if it is plugged into a SATA II or SATA III port on the Mobo.

You are correct that a drive only spins so fast, but just because SATA II does not saturate the interface, doesnt mean SATA III wont get closer. You should at least get better burst speeds and a millisec or so faster search time

http://www.youtube.com/watch?v=gk9oGRAxo6U


And if you consider the price between comparable drives, you will see the difference is negligible. Might as well get the newer SATA III drive.

750GB SATA III 6Gb/sec with 64MB cache = $79
http://www.newegg.com/Product/Produc...82E16822136794

750GB SATA II 3Gb/sec with 32MB cache = $69
http://www.newegg.com/Product/Produc...82E16822136283

So for $10 extra bucks you get double the cache, and at least a millisec faster search time, and faster burst speeds..... Seems like a deal to me The price difference is even less when comparing the 1TB drives.

SataII 32MB cache 1TB = $87
http://www.newegg.com/Product/Produc...82E16822136284
SataIII 64MB cache 1TB =$89
http://www.newegg.com/Product/Produc...82E16822136533


I use one as my main recording drive, it does great.