Intel Rapid Storage Technology *REDUCES* SSD performance! - recommend REMOVE

Sorry if this is in the wrong place. This is for my M17x brothers since I cannot speak to the results of other laptops/chipsets.

Guide Laptop sata speed data base...end user input needed - Page 5

 

never saw any issues with before or after installing the RST drivers. Wonder if it just has to do with OCZ SSD's?

 

It's not an issue per se, and not something one would notice with a stopwatch either. But since some of us are going after trying to eke out even smaller performance gains, I thought it might be useful. YMMV, don't know if this stands to benefit anyone with a non-OCZ SSD.

We can definitively know how other SSDs work with/without RST since Crucial M4 and Samsung seem to be popular here.

 

Interesting. I'm running an M4 009 with RST. The only thing I noticed was resume taking a little longer, but I think that is because what I have running.

 

Isn't that a SATAIII SSD? I get around 450MB/s on sequential read on my Crucial M4. I have RST installed as well.

 

I removed RST. With it, my boot up was about a second or 2 longer.

 

oh man, I use OCZ Ability now......

thanks for information, I will give it a try......

 

Well yes, .....yes it is.

 

Thanks for posting this SuperDave rep+

Could be a sandforce 2281 with 25nm nand issue though. My M4 is running in the upper range of M4 benches and I have the RST installed

 

Slick, Intel RST will be beneficial for you since you use the RAID controller. I'm going back to the RAID controller myself, since I found it faster by 1-2 seconds over AHCI.

 

hmm guess ill uninstall it for now and re-install in RAID next time I do a system format

 

That is correct, I am using RAID. Interesting observation. I always suspected that RAID was better for the M4 but I haven't done any real tests on it.

Geo, you're paying attention lol

rep+ for the info

 

Should i uninstall it for my hdd setup?
750x2 Raid 0

 

Probably not. I only compared SSD performance using ACHI, not magnetic HDDs on RAID.

 

Do you mean that the best performance option is to set RAID in the Bios instead of AHCI? (plus install Intel RST drivers)
Even if you will not build a RAID? (SSD + HDD)

I have just received my new Crucial M4 SSD and I need to know this before install the OS.

 

If you have 2 identical SSDs, RAID them together. If not, leave it as AHCI. However, in a single SSD setup, I have not seen any instances where choosing RAID in the BIOS improved performance relative to AHCI.

Regarding RST, your experience and results maybe be different considering our different brand SSDs. I can only say to try both scenarios (benchmark before and after RST on a freshly-installed system using ATTO, AS SSD and/or Crystal Diskmark) and share your findings with us.

 

My configuration is the same as SlickDude80: Crucial M4 + 320 Seagate HDD.

 

I have my BIOS set on RAID, not AHCI, with a M4 128GB SSD and Momentus 750GB HDD. Without having Intel RST installed, my SSD performance is worse. Read and write speeds are both improved with RST installed.

 

Wow!
Thanks for your answer.

But.... why?
Why the system runs faster when configured as RAID instead AHCI?
Does it happen in every PC or only in some circunstances?

 

First of all, I have the bus configured in RAID mode

I don't think the system runs faster configured in raid. I believe it will run slightly faster in AHCI but its marginal...meaning, my read and write numbers are right up there with those that use AHCI, but the boot up is faster in AHCI

However, I believe that the M4 is more stable in raid mode. I don't have quantitative numbers to prove this. But I got this from various conversations that I've had and from personal experience

So, the point is, IF you do decide to use RAID mode instead of AHCI, make sure you install the RST as you will benefit from it

 

Intel recommends that the BIOS be set for RAID and RST be installed even when the drives are not configured in a RAID array. Apparently, there are some settings in the configuration that are optimized and overall better results are anticipated. I believe with the BIOS set on RAID with RST installed with a single drive, the chipset uses AHCI mode in a manner that is enhanced.

One big advantage to doing this is that you can later add a matching drive to your computer and use the Intel RST Control Center to create a RAID0 setup without having to reinstall Windows from scratch, tweak registry settings or fuss with F6 drivers. I've done this a few times and it works nicely.

 

Mr. Fox, if I'm running AHCI right now and I want to go into BIOS and change it back to RAID, do I have to do anything special? Will it blue screen like it does if you try to go from RAID to AHCI? I have Intel RST installed already but I have the BIOS set to AHCI.

I want to try it the other way and benchmark my SSD again but I don't want to have to reload Windows tonight. Also, if I do switch it back to RAID, do I need to go into the registry and disable AHCI? I've done this going the other way many times but I've never tried to move from AHCI back to IDE or RAID. Back in the old days when IDE was still common and AHCI was new, I used to have to routinely switch this on laptops at work that shipped to us in IDE mode instead of AHCI. I've never had to go back the other way like I'm considering doing now.

 

I'll be interested to know your results, Jody.

 

jody, you can't do that...you have to reinstall windows. If you go on google, you can find some registry tweaks that will allow you to switch between AHCI and RAID, but they don't always work for everyone

 

OK. I'm glad I asked. I would've been upset if the whole thing fell apart. I'll have to wait until this weekend so I can make some ghost images of the drives before I start fiddling around with this. I'm assuming that if I built the windows install on the SSD from scratch and then make an image of it, I should be able to image it back without having partition alignment problems... I hope.

EDIT: I got all crazy and enabled the RAID driver in the registry and tried it anyway. I can't tell enough from the benchmarks to see that anything is statistically different running one way or the other. I've attached the benchmarks for your consideration. I disabled RAID again and put it back to AHCI because it boots a little faster since it doesn't have to display that RAID screen. My machine boots in eight or ten seconds usually. I've disabled the Windows splash screen which shaved off a couple seconds.

First thumbnail is AHCI and the second is RAID. I didn't disable anything that I normally run (temp monitor, desktop gadgets, MS Security Essentials, and suchlike)

 

Ya your numbers are a wash between the two

which firmware are you on?

I just ran a bench for you compare your numbers with. I'm on firmware 0309...and your numbers look right for a 512gig M4

 

I'm running 0309 too. I am not well versed in the ins and outs of each benchmark number. I know it runs pretty darn fast and I think it's the best upgrade I ever put in my computer. I'm trying not to over analyze it too much and go all OCD over it. I think I have all the right tweaks and the right firmware. I was never sure if I should be running AHCI or not. A lot of places recommended it so that's the way I went. The results seem to indicate either way would be fine for this particular drive.