New SSD. Troubles enabling AHCI.

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Gawd
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I just installed a new SSD. A 512GB Samsung 840 Pro, I plan on making it my boot drive with a fresh install of Windows 7 but just thought I would install it first and make sure everything was functioning properly.

I installed Samsung Magician and it sees the drive, but under the System information it says that AHCI mode is disabled and that it is also unable to detect the SATA interface details.

I have AHCI enabled in the bios, both on the 3 and 6GB/s ports, and I am also certain I have the drive plugged into the SATA 3. It's quite easy to tell as there are six grey SATA 2 ports and 2 red SATA 3 ports.

Could this be an issue with my mobo not being a native SATA 3 board? I think it uses a Marvel controller.

Ideas?
 
As a boot/OS drive you will be far better served using the Intel SATA2 ports than using the Marvell SATA3, especially on the X58 chipset. As an OS drive, in general usage you will rarely be breaking SATA1 speeds let alone SATA2.
 
I don't know about not breaking sata 1 speeds given the drive he will be using, but yeh the marvel controllers on many boards did not like SSD being used for one reason or another, Intel sata controller may not give as much available speed but it should also function as per designed which is far more important :)
 
I would also suggest using the intel sata2 ports rather than the marvell sata3 ones, thats what I do with my ssds. Also using the x58 platform here and the intel sata 2 ports are fast enough.

When I setup my x58 platform when the i7 930 cpu came out, I looked to see what was the better port to use and after reading it was shown that the intel sata2 ports were actually slightly faster than marvell sata3 ports.

Going by what you describe, it seems that your pc is in ide mode, and you just connected your ssd to it to test if it was working and expected ahci to be enabled, thats what i get from your post, I could be wrong a d if so then the following wont apply to you.

To get ahci mode you need to enable it in the bios, which you have done and then install windows, if you just enabled ahci in your bios and already have windows installed, it will not enable ahci. You really need to install windows from afresh to get ahci, ok you can fuck with hacks, but you are best starting from scratch.

Plug your ssd in and then Install windows and it should be ok, if its not then connect your ssd to the intel sata 2 ports instead.

If ahci was already enabled and working properly before and if the ssd doesnt show as ahci enabled in any sata 2 ports then I dunno.
 
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http://forum.corsair.com/forums/showthread.php?t=86403

You can force AHCI after install but yes you are most certainly correct it is better if done from first install. Generally you can do it via Intel based AHCI drivers or the default windows ones, it depends on which one works the best overall. Also of course if you have mechanical drives that were set to IDE and you try to force AHCI they usually freak out.
 
It's a 512GB drive so more than the OS will be going on it. Primarily games, and I'll probably throw my web browsers on there too to make them snappy.

This SSD is the first time I've plugged anything into the Marvell SATA3 ports, AHCI was not enabled originally on those or the Intel SATA2 ports in the bios. I ended up setting both to AHCI in the bios after encountering this issue in Samsung Magician. In windows, oddly enough, when I checked the registry as mentioned in that Corsair forum post, that 'start' value was already zero. So it sounds like Windows already had AHCI enabled? Perhaps because of my PCI-e SSD?

It's a little disappointing to think that the Marvell SATA3 could be slower than the Intel SATA2, not to mention I bought one of the fastest SSDs available and I won't be able to take advantage of it. It still seems odd to me that Samsung Magician can't determine any SATA interface details either. So frustrating.

I feel like there should be more options here...or should I just accept this Marvell controller is garbage and run the SSD through the SATA2 ports?
 
do a speed test to see how fast or slow both are and go from there. AS-SSD and ATTO are the 2 most popular ones. I would not advise constantly running benches but it may help to see what is the fastest for you and/or if the sata 2 will work fine. Keep in mind it is unlikely that you will match the speed the maker in this case Samsung has posted, usually with 5-10% loss is expected.
 
I just ordered a Samsung 840 250GB to replace my Intel X-25 80GB
I was hoping the change to SATA3 would reduce boot imies and increase performance in general.
Im using an X58 ASUS Sabertooth.
Will i not see an improvement?
 
I just accept this Marvell controller is garbage and run the SSD through the SATA2 ports?
Click to expand...

Do that. You will still be able to use the advantage of the 840 Pro on the SATA2 interface. I mean look at game and desktop benchmarks. I do not see any of these stressing the SATA2 interface. I mean do you see 300+ MB/s anywhere in real world application performance?
 
540-450 vs 250-100 umm yeh if you do not see a difference there is something seriously wrong however that being said, both are still very fast.

You should not notice the difference in real world apps/games and so forth when maxing out sata 2 or just tapping into sata 3 both are very fast. 300mb/s is like most raid setups and is extremely fast, but if comparing the drive running at provided speeds due to limitations or it running what it should be there should be a noticeable difference even if it is slight, like a Ferrari or a tuned Ferrari the difference would be subtle at best I imagine, unless you are seriously using the speed for things such as ripping movies and transferring them back and forth or doing "work" but just general usage I concur it will be plenty zippy.
 
Well I use that PC strictly for gaming. So I guess ill just use that 250 Samsung on SATA2 as a games drive.
Unless you guys think it would be better to put it on SATA3?
 
Another vote for the SATA2 interfaces. In real world you would not really see a difference between an Intel SATA2 and a SATA3 inteface, they both would just feel fast. One would just benchmark higher than the other. Same for the problematic Marvel controllers. I have had nothing but problems with them, and benchmarks only tell part of the story. There also seems to be some type of latency on those controllers, where it almost seems like there is a hitch each time it has to access the drive on a Marvel controller. The Intel SATA2 is the best path until you get a newer board with a newer chipset.
 
I'll echo the recommendation to go with the Intel SATA II ports.

It's been my experience that Marvell SATA controllers are disappointing. In particular, I've noticed mysterious delays, and incomplete or broken SATA implementation.

I encountered the latter when trying to use the eSATA port (powered by a Marvell controller) on my older desktop. It simply did not implement hot swap, which is supposed to be part of eSATA.

I had a similar problem when running Linux, which is why I think it was a shortcoming in the Marvell controller itself, rather than a random Windows/driver problem.

All this was on an Asus P5E3 WS Pro motherboard. I attached an internal SATA-to-eSATA adapter to one of the SATA II ports provided by the Intel X38 chipset (ICH9R controller, I believe). As if by magic, hotswap started working for eSATA connections made on this port.
 
Thank you for the input everybody, not the solution I was hoping for, but very helpful none the less. I think I'll put a little bit more effort into getting AHCI and SATA3 happen when I get home from work, but from the sounds of it I'll be going with the Intel ports for simplicity.

This is making me want to upgrade my CPU/mobo, which is a little disappointing, as I was thinking I might be able to stretch it out another year or so (I just bought 2 GTX 780s). I've done a bit of research and I just wasn't seeing the need when I have a mobo with USB 3.0, SATA3 (errrrr, not so much), and 3 16x PCI-e slots, and a processor that should be able to keep up with the newest games. I can't decide what chipset I'd go with either, x79, or x87, both seem to be lacking in one way or another. Older and powerful vs shiny new features....but that's another thread.

In the meantime, if anybody happens to have a solution for me as far as getting SATA3 and AHCI going for my shiny new 840 Pro, I'd love to hear it; I reckon I have about 3-4 hours before I say 'efff it' and just connect it to the Intel SATA2 port.
 
Perhaps I missed this as already done.
Disconnect the other drives, set AHCI in BIOS and just install the new OS.
Check what Magician says and move the cable to different ports, then check magican results.
Also try Cyrstal Disk info - but be sure sure not to accept the garbage.
http://crystalmark.info/?lang=en
 
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So I'm home from work and I figured I just try the other other SATA3 port, and what do you know, it seems to work. Samsung Magician sees it at AHCI and SATA3. Maybe it was a bad port? Funny, I tried that just as Britgeezer was suggesting it.

Still now I wonder if I should keep it on the Marvell controller as people talk a lot of smack on it. The Intel SATA2 could be better. I'll try some benchies I suppose.
 
dragonstongue said:
540-450 vs 250-100 umm yeh if you do not see a difference there is something seriously wrong however that being said, both are still very fast.

You should not notice the difference in real world apps/games and so forth when maxing out sata 2 or just tapping into sata 3 both are very fast. 300mb/s is like most raid setups and is extremely fast, but if comparing the drive running at provided speeds due to limitations or it running what it should be there should be a noticeable difference even if it is slight, like a Ferrari or a tuned Ferrari the difference would be subtle at best I imagine, unless you are seriously using the speed for things such as ripping movies and transferring them back and forth or doing "work" but just general usage I concur it will be plenty zippy.
Click to expand...

The Ferrari vs a Tuned Ferrari analogy isn't really relevant here. Because of the general workload of its use as the boot/os/apps drive, it is more like being in Manhattan. All things being equal, whether you have a Ferrari (SATA3) or a NYC Yellow cab (SATA2), in midtown traffic (low/mid queue depth 4k random transfers) both will get you to the same place at about the same rate. Maybe the Ferrari will beat a red light here or there, but overall both are constrained by everything else happening that is beyond their control.
Unfortunately, things are not at all equal here. Above and beyond that, especially with the X58 chipset, I would rather use the SATA2 ports that come off the PCH than use the marvell SATA3 which are connected along with god knows what else to a shared PCIe link of unknown depth.
 
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AS SSD benchmark:

Intel SATA2
SATA2%2520AS.jpg



Marvell SATA3
SATA3-%2520AS.jpg



So writes and access time are faster on SATA2, and for the most part reads are faster on the SATA3, overall score the SATA2 gets a higher score. Oh, that and the first time I did the bench on SATA3 I got an error on the read access time. So if I'm to put any weight to these results it looks like I'm confirming the Marvell controller really is junk. I'd love somebody to tell me I've missed something and things can be tweaked so those SATA3 results fall more in line with what you would expect, but for the moment I'm going with the Intel, like most had suggested without these benches.
 
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I would take the faster writes any day of the week myself, the reads are very fast to begin with and there is a chance that after using the drive for awhile it will arrange things better and those numbers will be a tad higher as well compared to when you benched it.
 
That's truly an eye-opening result! Thanks very much for posting it!

It's interesting to note that the sequential read and writes fall well short of the advertised "best case" specs for this drive - 540 MB/s and 520 MB/s for read/write, respectively, on the SATA III port.

Of course SATA II would max out in the neighborhood of 384 MB/s (3.0 Gb/s) but you're not even seeing that, when it's on the SATA II port. You see maybe 2/3 of that.

Anyone know why that is?

Possibly the CPU is becoming bottlenecked, as it's an older CPU in an older chipset?

This makes me want to re-benchmark the SSD in my desktop, just for curiosity. I have an Intel 520 SSD (aka "Cherryville) 120 GB, which is SATA III and claims up to 550/500 MB/s read/write. Even though I have it on a SATA III port, on a Z77 motherboard, with a fairly new CPU (details in my signature), I'm pretty sure I don't get anything close to that.

Makes you wonder what testing methodology the manufacturers actually use.
 
Of course SATA II would max out in the neighborhood of 384 MB/s (3.0 Gb/s)
Click to expand...

I thought the theoretical maximum was 300 MB/s since SATA encodes each 8 bit into 10 bits.

https://sites.google.com/site/ee3550usbesata/encoding

I'm pretty sure I don't get anything close to that.
Click to expand...

You should rarely hit that number in real world applications unless you have a high queue depth (probably by running several applications at the same time) or are reading or writing large files sequentially.
 
The cpu has very little to do with this and provides ample bandwidth either way and would not be a bottleneck as you put it, Sata is part of the southbridge if I recall in older chipsets and was still given more then enough bandwidth A and B the cpu is easily matching this in speed even an older one.

The problem is with the sata 3 being used in x58(which is a modern chip and chipset by the way) it is made by marvel and it is first gen more or less and does have quite a bit of issues and a lot more overhead then it should be given, part of the reason you see it not getting the speed it should be.

Sata II does lose a bit of speed as it does have overhead, so does sata III and PCI-e as well for that matter.
You should be able to hit close to that speed if all is running well, but there will always be a minor loss as all chipsets, programs etc do not run perfectly the same so results will always vary by a little. I know my Agility 3 60gb when I tested it new and approx. 6mths ago was getting between 2-6% of the performance it should be or 500-450 or so sata 3 on my AMD AM3+ chipset.

http://en.wikipedia.org/wiki/Serial_ATA
Second generation SATA interfaces run with a native transfer rate of 3.0 Gbit/s, and taking 8b/10b encoding into account, the maximum uncoded transfer rate is 2.4 Gbit/s (300 MB/s). The theoretical burst throughput of SATA 3.0 Gbit/s is double that of SATA revision 1.0.

It runs with a native transfer rate of 6.0 Gbit/s, and taking 8b/10b encoding into account, the maximum uncoded transfer rate is 4.8 Gbit/s (600 MB/s). The theoretical burst throughput of SATA 6.0 Gbit/s is double that of SATA revision 2.0.
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There is also things like NCQ to take into account, so while the drive may be limited to say that 300/s if the NCQ is tuned and allowed to burst you may see a more constant higher overall speed and much faster reaction times.
 
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