Seagate Momentus XT Hybrid HDD w/ built-in 4GB SSD

As far as I'm concerned, if you want the fastest drive and can't afford an SSD of the required space, get a momentus XT.... I have one and my access and boot times of all the programs I launch and the OS itself are increased by at least triple or quadruple what it was on my old (5400) drive. I'm very happy with it

edit: Since 500GB of storage in SSD would be over $1,000.00 you really can't go wrong with this drive.

 

The point to understand here is that the XT, like any hard drive, has no concept of a file. All that the XT's internal algorithms can work with is block addresses of data that are read from the disk. Regarding your question this means that the drive doesn't know nor care what size the files are that you open, all it knows is the data blocks your read from those files. So, if you regularly open, say, ten files that are 2GB each, and then read the same 64kB each from each of those files, then what the XT will put in its cache is the 10 pieces of 64kB of data you actually read from the files. Of course, if, every time you open the files, you read another random 64kB portion of the files, then the XT's logic doesn't have anything to work with, and you'll end up with transfer rates, and access times that are close to what you'd get from a standard 7200rpm drive.

 

Pirx,

I have a slightly different understanding of how the XT's algorithms work.

I believe it does not cache data at all - it caches the HD's directory entries. In this way, all files get a speed boost because the platters are not asked (constantly) where the next file is - the cache knows the location on the platters and simply sends the read/write heads there.

I do believe it caches programs though (exe, dll's, etc.) and keeps most of the O/S 'core' in its cache - this again benefits all disk accesses because it does not need to go to the platters to load a tiny bit of 'core' code to properly process the next data it will be using.

I'm not trying to correct you here - I think we are all guessing about how the nand's algorithm is setup and from my use with these drives and compared to how they respond to 'regular' HD's this is my best guess too.

To back up what I've stated above - I converted the same 2 RAW files over a dozen times (with no editing changes) within 5 minutes and there was no time difference from the first conversion to the last one. Each conversion was 6 seconds per file.

 

No, that is fundamentally impossible, and I can say that with confidence even though I know nothing specific about how the XT's firmware works in detail. See, the point is that the hard drive has no understanding of any kind of what a file or a directory entry is, let alone what kind of file it is dealing with. All the hard drive's firmware ever gets to see is requests, or series of requests, from the OS for certain block addresses. The hard drive does not and cannot know what kind of data these blocks hold. What the firmware can do is keep track of how often, in an appropriate metric, various block addresses are requested, and it will then keep the data at those addresses in its NAND cache. Typically, this cache, then, will hold bits and pieces of certain low-level data structures (such as portions of the MFT), as well as portions of files, or even some complete files. All it will care about is to have those data blocks that are read most frequently in its cache.

Don't worry, that's fine. But, as explained above, there are certain features of how the XT works that follow necessarily from the way a PC is organized.

 

as you can see with the discussion of pirx and tiller; and many more discussions in previous posts, no one really knows how the nand algorithms works.
your best bet is to analyze reviews with realworld data, like that of phil's, and see if these apply to your use.
the problem i think is that no reviews used 2gb data sets on xt tests.
as for me i see feasible increases on boot, shut down, and program startups (if opened multiple times).
i do some video editing also and i use files from 200mb to 1+gb but i really havent noticed any speed increase with regards to data read/writes (during video editing).
i was planning on getting an intel g3 ssd as a primary and moving my xt as an internal data drive. however from my experience, i would be better off selling my xt and using my old 5400 scorpio blue (or another 7200) for my data drive when the time comes.

 

What I guess I'm really going for here is random access read, on current projects. So say 10-20 songs/projects with large files. Since the thing stores read only, and I think I'm right in assuming that it isn't going to load an entire 2GB file, it's going to load enough to let the drive take care of the rest and still improve performance. What I'm going for is a better chance of no audio drop outs. These can occur with my older Hitachi 200GB 7200rpm drive. What it seems like is occasionally the disc gets over taxed and in return spikes the system. Sound silly, but it doesn't happen on CPU intensive projects, but ones with larg file loading in the middle etc. This isn't often, but I'm thinking that any amount of SSD memory at the beginning is going to take care of it.

 

if your using 10-20 2gb songs/files per project i seriously doubt if the xt is going to help.
if you want speedy random access reads in laptop i think your only options are ssd's

 

This is why most people check their authoring software forums to make sure their hardware is certified/compatible for music needs. Depends on how serious your are and what investment you have or plan.

 

I think the XT's algorithm is a little more complex than what you state:

Quote: "With more NAND Seagate could also prefetch data into the cache."

Source:

See:
Seagate's Momentus XT Reviewed, Finally a Good Hybrid HDD - AnandTech :: Your Source for Hardware Analysis and News

 

Actually, this article says exactly the same thing I am trying to get across: " The drive looks at access patterns over time (most likely via a history table of LBAs and their frequency of access) and pulls some data into the NAND. If a read request comes in for an LBA that is present in the NAND, it's serviced out of the 4GB chip. If the LBA isn't present in the NAND, the data comes from the platters."

One last time, all the drive can ever look at is LBA (logical block address) access patterns, period. It simply has no way of knowing what the data at those addresses might be.

Oh, and this has nothing to do with the algorithm being "simple"; the algorithm the firmware uses to determine what to cache or not may well be complex, although I suspect that in the interest of processing time it will be simple in terms of its software implementation. The mathematics behind it may well be complex.

 

Pirx, I am obviously misunderstanding what I'm reading (and also seem to be experiencing first hand with my XT's).

I will bow down to your much deeper knowledge in this area.

Thanks for trying to get some new information into this thick skull.

 

Momentus-XT-Momentus-and/Momentus-XT-Frequently-Asked-Questions

Re: Momentus XT Frequently Asked Questions - Seagate Community Forums

 

Most likely the math is complex. The reason is like a normal SSD the data to the NAND is compressed when stored. This also means decompression at read time. over all it is fairly impressive what Seagate has done here.

I believe what is meant by prefetching is letting an extra amount of NAND read and store the pressent track when the head has to move. as sequential files are read in a defragged drive the head usually has to do little movement. if you have enough NAND to store multiple tracks even better. the more tracks you can store the more seek time you save and storing a track can save on rotational latencies.

That all of course is theoretical and most likely contrary to pressent algorithms. Seagate would have to find a way to combine the algorithm further complicating the math or abandon the original setup all together. Sorry if off topic here as this really should be about the hardware as is not what should or should not have been implimented.

Back to topic; I have found with the XT it seems to accelerate a bit internet usage but not so much as a SSD. With a 15Mbs pipe the write IOPS just are not there for small files. So if you are visiting new pages and loading new graphics etc it works about as fast as a good 7200 or slightly better because of the 32mb cache. On frequently visited sites though it feels more like my SSD as pages and files etc are read and handily cached by the NAND.

Based on the increased readability of the XT and my SSD I personally have raised the default internet cache size to 256MB. This seems to be a happy setting as it tends to keep the files on drive rather than forcing new loading of them along with the drive having to now delete the old, or in the case of the XT having to recache them if needed later.

 

I would stay with SSD drive. It also reduces all-over-heat in my laptop..

 

Well, if you only need 120G, fine..how much for the 460 G model?

 

I have the XT in my U81-a and SSD in the P7805-u, Asus and Gateway respectively. I am relating my experience between the two. For a short time I was using the XT on the P7805 as well. I probably should have been clearer.

I appologize for that, I just suddenly lost my mom last week and burried her tuesday. Now I'm brain dead in the middle of Estate issues..........

 

So are spindown and 'turn of hard disk' in Windows advanced power settings 2 different effects?

Spindown does not keep the drive from idling, correct? Does it increase power consumption?

 

lol, I guess it all coems down to useage model...


I know my old M1210's 80GB drive has not been a limitation, but that's just me. I know, for sure, other people have (often) radically different drive usage requirements.

I kinda "upgraded" so far. I put a bid in for a NBR member's FS OCZ Vertex 2 120GB. It's be a nice upgrade for me, not just in speed, but also in capacity (though the scratch space is likely to take up a good 10+ GB...).

 

Should be the same thing. Though some drives are known to ignore what windows tells it to do (some WD drives, iirc).

 

from what ive read in this thread and others, switching the power settings to high performance did not solve the issues, but the latest firmware did.
probably for the reason that jeremyshaw mentioned

 

Installed an XT and fresh Win7 on my X200 yesterday... and it's driving me mad!! Definitely fast but increased noise, vibration and noise (over boggo 5400rpm factory Hitachi) is driving me insane. Don't get me wrong - it's not excessive to indicate a faulty drive but I'm just fussy! Upgraded to latest firmware but it was never really going to make any difference lol as it wasn't the chattering issue. Think I should have stuck to gunning for an SSD - in fact, looking now. All in all, a good drive but perhaps better suited in machines with slightly better mechanical and acoustic damping than the X200 IMHO.

 

well my xt is as quiet as my wd scorpio blue

 

See about exchanging it because that sounds faulty. I was impressed at its relatively non-existant noise and vibration compared with the regular Momentus 7200RPM it replaced.

 

So the new firmware keeps the drive from spinning down but does that allow it to play better with Windows power settings?

I want the drive to spin down after 5 minutes of inactivity on battery, though I don't think my current one listens to Windows either.

Even while spun down, the drive is still 'listening' so to speak, it's not totally cut off from power so what could I figure is the consumption difference between parked and idle?

 

In my case; I have 3 laptops and one destkop. I have everything on my 1TB WB external hard drive, and my 1TB WB 2.5" drive. So, 120 GB is more enough for Vista x64 and my games.

 

here's my experience flashing the firmware: ordered one of these and got here from newegg.com yesterday, came pre-installed with SD23 firmware but to be sure I had the same firmware that disabled the spin-down (also listed as version SD23), I attempted to use the update utility from Seagate's web site. anyway reboot and it runs, it detected my controller type (Intel Series 5/3400M) and the drive model/serial/fm. version, but didn't say whether it was updating or not after that. It didn't give me any further status updates and I ended up having to manually power it down, but everything still works. Definitely bad design to not give a status message if they aren't going to flash or say what's going on, rather than leave you at a detection screen.

 

I tried to flash the new firmware over mine when I got it new, and it came up with a message telling me that I already had the newest firmware installed and that the process was aborted, then immediately rebooted the computer. It was quick, maybe you missed it?

 

My XT is quiet as hell.. i had a 5400rpm toshiba which was just so loud.. its basically to do with the laptops's design.. You might have to try different drives... try getting a hitachi 7K500 drive instead.. it should be quieter for sure... you might have a faulty drive so i'll try a RMA..

 

i have no idea about the power difference.
my laptop is always on high performance. i never use battery too

 

Has anyone been able to ascertain if the momentus xt 250 one platter design is quieter than say the 320 or 500? I recently purchased the 320 because it was on sale but I read the 250 maybe quieter?

 

bummer, mine must have been completely glitched - i used the Windows based installer though (it starts in Windows, reboots into custom Seagate flashing environment), maybe it works differently for the CD boot image? it stayed on the hardware detection screen, no reboot, wouldn't respond to anything after many minutes. no status messages regarding whether it was or wasn't flashing the firmware.

 

i also used the windows based installer. weird, crazy things always happen!

 

I saw this mentioned a few threads back but that was it. Is the jury still out on whether the 500gb model will operate quicker than the 250gb because it has 2 platters to short stroke instead of 1?

 

RWUK,

In my mind I believe the 500GB 2 Platter model will be the better 'performance' buy because it will allow for a larger 'C:' (or, in my case; a 'T' = temporary drive) or, the same sized partition using a smaller % of the total capacity.

To see what I use a 'T' partition for:

See:
http://forum.notebookreview.com/har...-hitachi-7k500-benchmark-setup-specifics.html

 

Hey there,

I'm new to Seagate Momentus XT and was wondering, if it's a hybrid drive, then should I defragment it sometimes or just leave it as it is.

 

You can treat it like a normal hard drive. It's good to defragment.

Edit: I was wrong. Read MassiveOverkill's post below.

 

Doesn't it reset the "learning" at that point? Or does it rebuild it very quickly? (I kinda imagined it would take a while...).

 

Turn off defrag or set its schedule less frequently. Also auto A/V scanning is recommended to be turned off as well as prefetch:

Momentus XT Enhancements

 

I got a 500GB xt yesterday as a small sunday project. $129 at Tiger. I am amazed that the seagate copy tool does not disable windows sleep for drive cloning. But after sorting it out, the typical reboot test after 3 boots cut boot time in half.

Now I see the enhancements posted! Cant wait to try them. Oh, and my drive is super quiet.

 

Ok Here goes.............

1.) Often defrag is not a plus with the XT. As you move files around you force the NAND to have to cache those files all over. your best bet is to defrag still but to do so once a month or so. YMMV with this but as good rule of thumb is by your previous optimal defrag pattern to increase it 4-8 fold in length between them.

2.) A/V scanning, you force the NAND to cache assorted files you will probably never normally use kicking out files you do use. The common user should never stop this but reducing frequecy of this will increase consistency of the drive.

3.) Superfetch diabled, With Some configurations disabling will help. This is for those commonly not using MS products beyond the OS. IE strictly gaming or those using say Open Office and a mozilla browser. Superfetch precaches alot of controls, .NET, etc. that are preloaded by Windows 7. if you do not commonly use these files preloading, and the drive caching them, is a waist. I use IE and MS Office along with Visual Studio at times so superfetch serves me well.

4.) Personally I use the Intel Matrix manager. I haven't benchmarked any differences with the XT but since they work great with my SSD I like to be consistent.

Again with all of the above YMMV, and especially with A/V take care. Sometimes security is better than raw performance.................

 

well said tanware +1

im also thinking that if you have 8gig or so of ram it may be better to leave superfetch on

 

switching to a completely manual defrag schedule is probably best, only do it whenever you know you've made a lot of changes to your hard disk and you want to get things re-ordered and restart the XT's caching patterns, that's when you defragment. everytime it's done, you're interfering with the drives ability to properly track and speed up files - consider the process reset every time it's done.

A/V and other automatic file scanning and management tools will almost have the same effect, if you're savvy enough, disable them completely. It is possible to run Windows without worry of infection and without antivirus software if you just watch what you're doing in terms of programs you install and what you allow to run, and with Vista/7's UAC and better security, it's even easier to do. I've never had a legitimate infection on my Windows ME/Windows XP/Windows 7 machines and I haven't used antivirus in 10+ years, except for occasional manual scans. Disable CD/USB auto play if you must, keep updated, and don't install a bunch of crap or warez on your system, or anything you don't know or specifically need for something.

 

Well me, myself and I won't even sweat a defrag. I never really saw much point in any of my drives, as in normal use I may see 10% after a very long time. I figured I did far more drive wear and tear after a 6 hour defrag over night?

I normally end up just doing a clean install due to bad upgrade because I just can't leave well enough alone or that new driver just hosed my files!

 

Thank you for that link, I had lost it when my other computer recently crashed and haven't gotten it up and running yet.

1) I only defrag about once a month as it is. I do notice gains in Crystal Disk but not so much in everyday use. IIRC the NAND is not factored into the 500gb of disk space, it's function is more for memory but the frequently used files are physically stored on it. Is it possible to clone the NAND state before defrag? If it can be loaded back into the drive's memory afterwards, this would eliminate the time it needs to relearn everything. I'm guessing this isn't possible now because it seems there's no way to (through software) tell the NAND apart from the disk. Would be nice if this was available in Seagate tools, or maybe it is? I've never used it.

2) Are you referring to on demand, full drive scans or real time scanning? A typical licensed or 30 day trial AV program simply running will take up memory and nand space because of the real time scans plus update checks and downloading.

Somewhat related, is this an area where disabling unused and unncessary Windows services would make a more significant difference than on a regular disk drive?

4) Funny you mention Matrix Manager. Intel Rapid Storage Technology which is supposed to be the update to MM has given me lower Crystal Disk scores when I recently switched. Removing RST has also forced a needed OS reinstall. Maybe it works better for the XT though. I was hoping to do a comparison until...Windows broke.

I'm really trying hard not to jump on a 500gb Scorpio Black right now. They're $10 off at Newegg until Wednesday so it's $65 shipped vs. $131 for the XT. I'm just either trying to convince myself that the XT is either not worth the extra money or IS worth the extra money! Boot times aren't nearly as important to me as everyday use and with a clean install plus all my stuff on a quick disk drive, I can deal with a 45 second start up for under $70. My Photoshop CS5 did open in 5 seconds, no lie. Opening a ~100mb psd and CS5 at the same time would be around 11sec. At the time of my Windows failure, I was getting 95/85 mb/s read/write speeds on my 7200.4 with Intel RST and immediately after a Perfectdisk defrag.

And last, are WD or even Hitachi planning to release a hybrid of their own? I think claims that the G3 Intel SSDs are going to suddenly make everything so much more affordable are hard to believe. $100 off a $500 drive is still half the price of many people's notebooks.

 

I'm sure this has been explained before, but no that isn't possible. The NAND cache doesn't keep track of files or even know what the data is that it's working with (or that it's even part of a file system/etc). Logic is telling me that the drive only keeps track of the sectors/areas on the hard disk and how frequently parts get accessed, when a file gets read all the hard disk sees is calls to the sectors/areas on the disk itself, and it chooses then to pull most frequently accessed areas to the NAND cache. When you are defragmenting your hard drive, the drive has no knowledge of what data is being read or written to the disk because the data is being pulled into memory and manipulated with software before it's re-written, and to the hard disk it has no way of keeping track whether or not that same data being written on another sector was the same that was just being read/changed in another. Although I'm sure it's possible for them to build some logic to read and keep track of the most popular filesystems, I believe they've said it works independently of them and regardless of the data stored on the disk. You could have random data without structure being read and written and it'd still keep track and cache the most frequently accessed areas.

 

Any news on XT drives larger than 500GB? A 640GB would be quite nice.

 

Hey guys, since this thread is active and I didn't want to create my own thread, I'm just gonna ask my very simple question here.

Is the Momentus XT compatible with my Vostro 1500? If it is, are there any caveats?

Thanks

 

It'll be perfectly compatible in that it'll fit and work.

I don't know if the Vostro has SATA I or II. If it's SATA I it'll work fine, just not as the tip-top speeds SATA II users have.

 

Thanks for the quick response. I'm pretty sure it has SATA I or SATA 150. Is it going to be a major caveat, not being able to use the Momentus XT (a SATA 300 drive) with a SATA 300 controller?

 

It should still perform pretty well, burst read speeds might be slightly hindered but not by much.