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View Full Version : Is 16 mb cache on hard drives another gimmick or?


Treason
01-29-05, 12:08 AM
So now we are beginning to see 16 mb cache on new Maxtor hard drives, particularly on the 200 GB ATA and SATA models.

However, I've noticed that the price difference between the 200 GB 8 mb cache and 16 mb cache models is negligible. (at least at the local computer store near me < $5) The margin is larger for the 250 GB model.

So before I recommend a friend to grab a Maxtor 200 GB 16 mb cache ATA, is 16 mb an advancement for us "old tech" ATX/AGP or is it geared toward the BTX/PCI-Express machine? Does it make a difference at all? Is it just a marketing gimmick like AGP 4X vs. AGP 8x?

jAkUp
01-29-05, 12:13 AM
It actually is very fast, the maxtor 300gb comes very close in performance to a 74gb raptor

gate1975mlm
01-29-05, 10:17 AM
It actually is very fast, the maxtor 300gb comes very close in performance to a 74gb raptor


Yep great drive!

$n][pErMan
01-29-05, 01:18 PM
what ... what? I noticed almost no difference between 2mb and 8mb .... and now they have 16mb and expect me to think its gonna be the best thing ever!?! I noticed a better increase from IDE to SATA.

jAkUp
01-29-05, 01:27 PM
I noticed a difference from 2mb to 8mb. The difference can be up to 30% faster.

$n][pErMan
01-29-05, 02:02 PM
I suppose if you did some sort of hard drive benchmark you would see a difference. But honestly... I noticed more of an increase in load times and write times by OC'ing my CPU :p You have me curious now... think im gonna dig up my 2mb hard drive and use it ... and see how much slower it is.

Greg
01-29-05, 11:36 PM
Imagine what will happen when someone puts.... 32mb cache on the drive ;) Really, the more cache the merrier. Cache on the drive does improve performance, systerm RAM used as cache also helps if you are reloading the same data.

Edit: This is a great place to go for HDD reviews and info: http://www.storagereview.com/

Nutty
01-30-05, 12:39 PM
But considering RAM is soo cheap, why dont they put 256 meg of PC133 ram on as cache or somat?

The reason I suspect is prolly more likely to get corruption on power failure being unable to write all that data out.. Do current drives still manage to flush the cache on power failure ?

$n][pErMan
01-30-05, 01:04 PM
The reason I suspect is prolly more likely to get corruption on power failure being unable to write all that data out.. Do current drives still manage to flush the cache on power failure ?
Damn .. never thought of that!

Treason
01-31-05, 01:26 AM
So it looks like we'll have to wait for some official benchmarks to appear. Differing opinons. In the meantime I'll tell my friend to hold off the purchase.

CaptNKILL
01-31-05, 10:14 PM
But considering RAM is soo cheap, why dont they put 256 meg of PC133 ram on as cache or somat?

The reason I suspect is prolly more likely to get corruption on power failure being unable to write all that data out.. Do current drives still manage to flush the cache on power failure ?
Im not sure, but cache is probably a different kind of memory than normal SDRAM. Its probably more like the cache on (in) CPUs, which is very expensive. Obviously it isnt THAT fast, but its probably somewhere in the middle of DDR and CPU cache.

I really have no idea though. Cost, space, availability, stability... there are probably a lot of reasons they dont slap huge amounts of cache on them.

That said, id like to see benchmarks of a drive with 64 or 128mb cache. :D

Bubba
02-01-05, 07:30 PM
the price of cache memory used in new HDs may or may not be low - it's dependent on many factors just like other types of ram chips. It's a pretty safe bet, I think, to assume that the caches used in IDE/ATA devices are different than what's used in current system memory modules. If they're putting 16mb now on new drives, though, it probably isn't expensive to the manufacturers in relative terms.

As Jackup said, the new maxtors (specifically the 250gb and 300gb maxlines) are good performers. There've been a rash of new reviews on these too, so you should check those out. I think there was a recent posting for one of them in this very forum.

Bigger caches on these types of devices certainly helps specific types of performance. The jump from 2mb to 8mb gave great results.

Bubba
02-01-05, 07:36 PM
check out....

http://techreport.com/reviews/2005q1/maxtor-diamondmax10/index.x?pg=1

http://www.anandtech.com/storage/showdoc.aspx?i=2094

Treason
02-02-05, 06:22 PM
Argh, never mind. Looks like he'll be grabbing a 250 gb 8 mb cache one since he has an Athlon XP. Seems like the 16 mb cache ones are geared toward multi-tasking anyways and would benefit Intel users greatly.

Remember that to take advantage of NCQ on the MaXLine III, a controller and drivers with NCQ support must be used. Currently, only Intel's ICH6 features support for NCQ when used with the Intel Application Accelerator 4.0 drivers.

AthlonXP1800
02-04-05, 05:18 AM
Argh, never mind. Looks like he'll be grabbing a 250 gb 8 mb cache one since he has an Athlon XP. Seems like the 16 mb cache ones are geared toward multi-tasking anyways and would benefit Intel users greatly.

Remember that to take advantage of NCQ on the MaXLine III, a controller and drivers with NCQ support must be used. Currently, only Intel's ICH6 features support for NCQ when used with the Intel Application Accelerator 4.0 drivers.

Not just only Intel support NCQ, AMD has NCQ support with NForce 4 chipset and probably next VIA new Southbridge chipset will support it.

lightman
02-04-05, 07:00 AM
Im not sure, but cache is probably a different kind of memory than normal SDRAM. Its probably more like the cache on (in) CPUs, which is very expensive. Obviously it isnt THAT fast, but its probably somewhere in the middle of DDR and CPU cache.

Err. Not really. The mem chips of the cache of the new Maxtors are clocked at 150MHz ... ;)

Filibuster
02-04-05, 07:23 AM
Years ago (386/486 era) you could buy an add-in IDE controller (they weren't built onto most motherboards then) with 30pin simms on it for cache. :) It was really sweet back then because there wasn't even smartdrv to speed up the disk (ram was too expensive to be used for _that_)

RAID controllers today with cache have a battery to save the cache until it can be written to the disks when power comes back up. Maybe they could do the same thing on the hard disk, like a rechargable battery on it somewhere. Of course this would run the cost up significantly so it would only be worth doing once the caches got to be huge.

nIghtorius
02-04-05, 08:58 AM
the price of cache memory used in new HDs may or may not be low - it's dependent on many factors just like other types of ram chips. It's a pretty safe bet, I think, to assume that the caches used in IDE/ATA devices are different than what's used in current system memory modules. If they're putting 16mb now on new drives, though, it probably isn't expensive to the manufacturers in relative terms.

As Jackup said, the new maxtors (specifically the 250gb and 300gb maxlines) are good performers. There've been a rash of new reviews on these too, so you should check those out. I think there was a recent posting for one of them in this very forum.

Bigger caches on these types of devices certainly helps specific types of performance. The jump from 2mb to 8mb gave great results.

why would they put in faster memory in the disk since the SATA I/II interfaces only have a throughput of up to 150MB/s (SATA-I) / 300MB/s (SATA-II)

thus putting memory that's faster than 300MB/s (for SATA-II disks) would be utterly useless.

Bubba
02-04-05, 10:34 AM
I don't necessarily know what, if any, impact the cache ram speed would have in relation to the data transfer rate, but I do think it would interesting to better understand the correlation. Cache ram speed = frequency data is written to/from cache. Transfer rate = amount of data that can be sent over the interface. I'm sure there is dependency too on the algos and implementation used by the HD to determine how/when to cache, etc. Also, size of cache comes in to play there too. I think the whole point of cache on HDs is to have frequently used data ready to send so that you don't have the latencies involved with getting it off the disk. Don't know whether or not all data goes through there.