AHCI Vs. RAID

[andrewboon]

I know the difference between RAID and AHCI is that RAID is for people using over one harddrive or SSD. I am just wondering why people do it. Is RAID faster than AHCI when using two HDD/SDD? Or is it just fail safe? I am not sure why people use RAID. I am using AHCI right now with one HDD and one SSD and I am wondering if its worth it to reinstall Windows 7 all over again for the benefit of RAID. I tried to search online but can't seem to find any information that I can understand. A lot of the topics are using big words I don't understand. I am looking for a simple answer that a noob can understand. I'm using an Intel Core i5 2500k with a GIGABYTE GA-Z68XP-UD3 motherboard. I have a harddrive and a SSD (Crucial M4 64gb)

Also if you do suggest to reinstall Windows 7 in order to use RAID, how should I enable RAID? In my BIOS, I saw that there was a "GSATA3 CTRL" option to switch to IDE, RAID, or AHCI, and then there was a "PCH (something else forgot what it said)" and it had the options of IDE, RAID, and AHCI. Currently both of them are set to AHCI, so if I wanted to reinstall for RAID, would I switch both to raid?

Thanks for your help.

 

[fffblackmage]

The simple solution is to just leave it on AHCI mode and not worry about RAID.

On the Intel controller, RAID mode and AHCI mode is actually almost identical. The only difference is that RAID mode has the option of allowing RAID arrays.

Have you tried reading the wiki article?
http://en.wikipedia.org/wiki/RAID

It's pretty simple and easy to understand (or so I think). The most significant RAID levels are just 0, 1, 0+1, and 5.

One very important thing to remember is that RAID is not a backup.

If you still have questions, feel free to ask away.

 

[tweakboy]

I agree with fffblackmage. Their almost identical. Ive done research on this and FBM is correct...... I hear a echo in here!

 

[andrewboon]

So I should just leave it as AHCI? Also after installing this new SSD, my CPU temperatures seem to have gone up 1-2 degrees Celsius, I used to idle at like 25-27C and now I'm idling at 28-29. Is this normal? Or did I bump something while I was installing my SSD....

Also I won't be able to use Smart Response Technology or Rapid Storage Technology, will I? Because I'm using AHCI. I guess it's a special thing for Intel chipsets.

 

[Old Hippie]

A lot of the topics are using big words I don't understand.

I'll try to keep it simple.

RAID0 is probably what you're talking about when you combine the capabilities of 2 drives into a single imaginary drive but it will only perform like the slowest/smallest drive included in the array.

In your case it makes no sense to combine a mechanical drive with an SSD because it will perform like the mechanical drive.

RAID0 works great with SSDs and I use it to it's full advantage.

Short, sweet, to the point, and I can only but hope the words weren't too big for ya. :biggrin:

 

[andrewboon]

I'll try to keep it simple.

RAID0 is probably what you're talking about when you combine the capabilities of 2 drives into a single imaginary drive but it will only perform like the slowest/smallest drive included in the array.

In your case it makes no sense to combine a mechanical drive with an SSD because it will perform like the mechanical drive.

RAID0 works great with SSDs and I use it to it's full advantage.

Short, sweet, to the point, and I can only but hope the words weren't too big for ya. :biggrin:

So what you're saying is RAID 0 is only useful if you have one or more SSD's? Not a mix of HDD and SSD?

 

[Syran]

Really here, you have 2 options:
ACHI: Run windows on the SSD with some apps, storage and everything else on the mechanical hard drive
Raid: You are not looking to run Raid 0, however, you may want to look up SSD caching with the Z68 motherboard. It is an option, and it works fairly well. It is not as fast as running everything off of an SSD, but it is much faster then running everything off a normal 7200rpm hard drive. That's what I currently use on my pc. Samsung 64GB SSD in cache mode with a 2TB WD 7200RPM HDD. Works great.

 

[Old Hippie]

So what you're saying is RAID 0 is only useful if you have one or more SSD's? Not a mix of HDD and SSD?

Read what I wrote and think about it.

Why would you put a much slower drive with an SSD?

 

[Shmee]

usually raid 0 should be done with identical or VERY similar drives. You should stay with AHCI for now.

 

[wansurfer]

andrewboon,

What are you doing with the SSD, now? Are you using it as a cache for the hard drive or do you have Windows installed on it and you're using the hard drive as a slower kind of storage? Or, is Windows installed on the slower hard drive? Are you using the SSD as just a backup drive?

Your motherboard has an Intel Z68 chipset so it should support using the SSD as a cache for your hard drive. Though some people don't want to do that because they want to minimize writes to their SSD and maximize its lifespan. Personally, I would do it. FYI, if you decide to use the SSD as a cache then I think Intel's software will prepare the SSD by clearing any data that's already there. Also, you need to enable RAID mode in your motherboard's BIOS first, too. Unfortunately Windows usually doesn't like it if you just decide to switch on RAID mode after it was installed with AHCI mode. Usually Windows will show you a bluescreen error and quit if you change that option without preparing Windows for it. For your motherboard, I think, Gigabyte provides a little program which will give you the option to set up Windows and change the BIOS setting for IDE, AHCI, or RAID on the next reboot. I have a friend who has used it a couple times and he has a Gigabyte motherboard with a Z68 chipset. There's a Microsoft FixIt webpage where you can download a little program that changes the registry settings in Windows for you but you need to change the BIOS setting.

An alternative is putting Windows on the SSD plus some programs you want to start and run fast and then use the regular hard drive for slower storage. Though some programs won't run correctly if installed any place other than the boot drive which is typically labeled as C: in Windows and I expect that would be your SSD. If that's needed for some reason then you can try messing with stuff like folder redirection or mounting a drive to an empty folder.

If Windows is currently installed on your slower hard disk and if the amount of used space on the hard disk is less than the available space on your SSD you may be able to shrink the partition of your C: drive and then image everything onto your SSD. If you do that then allow for some breathing room. I wouldn't try it if the used space on your hard drive is 60GB and your SSD is only 64GB. It would probably work and Windows would start but that wouldn't leave you with much room to work with. The image programs that are more noob friendly will try to automatically resize the partition for you. [Has anybody tried that with Intel's Rapid Storage Technology software installed? I suspect it may cause screwy things to happen in Windows after you boot from the freshly imaged SSD so you may want to uninstall IRST before using the imaging software to copy the regular hard drive to the SSD. Or, try it with IRST installed and report back what happens. I'm interested.] andrewboon, maybe you don't have IRST installed already, anyway.

Edit: I looked back and now I see that Syran mentioned the same stuff I yapped about but he was much more concise.

 

[MrX8503]

If you want to use SRT, you need to put it into RAID mode. Just set it at RAID and forget about it.

There's two categories of RAID:

-Using a small ssd as a cache to speed up the slower drive

-Using multiple drives that are normally identical to create an imaginary single drive that is super fast.

 

[Old Hippie]

I looked back and now I see that Syran mentioned the same stuff I yapped about but he was much more concise.

And the thread is 1 yr old.

 

[Makaveli]

lol talk about a necro!

 

[wansurfer]

Whoa... sorry for grave digging. I'm not sure how I stumbled on to this thread.