SATAII VS SATA-300 VS SATA 3.0Gb/s

thirteenthcor

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So I have a few HDDs, all at 7200 and all are SATAII/SATA-300/SATA 3.0Gb/s rated...
I have a MSI 790X-G45 SATA 3.0Gb/s Mobo


The fastest transfer rates I can hit are 167Mb/s. I can only hit these numbers between one brand-new ST32000DM001 Seagate Barracuda (64MB Cache) and two RAID0 Seagate Constellation ES (32MB Cache) drives, and only even then when I make sure the two RAID0 Constellations don't share the same channel.

That's surprisingly only when I am writing TO the Constellation Array from the Barracuda. If I am reading off to the Barracuda the Array settles down at around 130Mb/s. I know transfers are set by the slowest drive, so either the write rate of the Barracuda is lower than it's read (by 35+ Mb/s?) or it's the reverse for the Constellations.

I checked the channels between these three drives as well, and regardless if the Barracuda shares a channel with either Constellation, it still stays at 130Mb/s when writing to the Barracuda.

-But-

Is this all I can get out of these drives? I have brand new SATA cables as well (though in most cases that won't matter).

I did a Google crawl and was inundated with data. I can only assume this topic has been hit dozens of times before, so I apologize in advance.

Is it that while my Mobo and SATA connections themselves can go "up to" 3.0Gb/s my actual HDDs top out at 170Mb/s?

Does anyone actually know what the maximum (even theoretical) Read/Write rates are of 7200 SATA 3.0Gb/s HDDs?

Another Google crawl on the subject revealed more obfuscation.

Ideas gents?

Thanks!

T.
 
max throuhput = RPMs as it translates to angular veolicy, The density of the magnetic domains on the platter. Writting to the drive starts at the outside edge of the platter and this will be where the highest throughput will be (highest angular velocity. As the platter is filled the closer you get to the inner part the the platter the angular velocity decreases.

On Your Raid0, if you want to get the best performance then use "short stroke" This is where when you create the array, you only use about 30 % of the avalable space. You live the remaining 70 % unused - ofcoarse for the gain in performance, you lose disk space. (Just google short stroke.

As mentioned - SSD are the way to go to improve performance.
 

thirteenthcor

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Thanks for the advice, that makes perfect sense about the discrepancies in angular velocity. Distance from center and all that.. Reminds me of Coriolis force? I would run a short stroke but I need the space+transfer rates of all my HD files.

Now I guess a related question:

Since SATAII/SATA 3.0Gb/s/SATA-300 (are these all the same?) Seem to offer theoretical transfer rates of obviously 3.0 GIGAbits per-second, and since SSDs look like they top out at a around 400-500Mb/s for Sustained Read/Write... Then what is the motivation for moving to SATA3 as a standard?

It would seem that if I went SSD for OS I would, as of this moment, notice no obvious change in performance between SATA2 and SATA3 based on drive performance. Unless I'm completely missing something.
 
Probably correct.
Most buy a SSD to speed up (A) loading ther operating system and (B) speed up program loads. Read/writes to the SSD are very fast. If between and SSD -><- HDD then 1/2 of the transfer is fast but the other half is at the HDD speed.

And here storage space is at a High cost, ie 150->200 bucks just for 128 gig.
 

caqde

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The only way for you to get good performance with lots of drive space without spending lots of money on large SSD's is to use caching programs like Romex's FancyCache (Caches data using RAM and/or SSD), NVELO's Dataplex (bundled with certain specific SSD's only), and SuperSpeed's SuperCache (Caches data using RAM).

I personally use FancyCache at the moment it boosted my PCMark score by 1000 which is pretty nice (2536 -> 3566) and lets me load my software a lot faster. I want to eventually get a 64GB or larger SSD to use as a secondary Cache.