Raid controlers

[miketsmith]

I can't seem to find a whole lot of information regarding raid setups.

Here's the deal: I currently have a core i-7 system, i was thinking about setting up a RAID5 array with four drives. I, however, can not seem to locate information on how to really read into the spec sheets for raid cards that are available.

I would like to know, first off, what kind of read/write speeds you can expect out of hard drives that are on the market now.

If sata II is sufficient, or if I should try to go with the 6Gb sata.

The performance benefits for running a raid 5 (I was thinking four drives, but I'm open to suggestion)

Suggestions on raid cards and hard drives (I don't want to go too expensive)

And any other useful information that can benefit me while I look at raid controllers and hard drives.

Thanks much.

 

[Wamphryi]

Don't set up RAID 5 it can be punishing when it comes to write speeds unless it has the worlds greatest RAID controller and even then it still can misbehave.

HDD speed vary. Green drives are typically slower due their 5200 RPM speeds. 7200 average out at about 90 MB a second while Velicoraptors hit 120-130 MB a second.

After a great deal of messing about I have found a single Velicoraptor is all one needs for a system drive. I have tried SSD and various RAID 0 configurations but the performance is not reflected in real world computing. The only RAID I use now is RAID 1 for its excellent redundancy.

Yesterday I installed 16 GB RAM in my system and scored Ram Drive. I place videos requiring editing in an 8 GB RAM drive and that performs very well. When I finish I copy the finished files to my RAID 1 and job done.

 

[miketsmith]

I want redundancy and speed, along with a fair capacity. I'd be willing to spend 1-300 dollars on a raid controller card, I just need to know what to look for...

What about setting up a mirrored striped array? or 3 drives striped with another drive with 3x capacity mirrored to that?
Is that even possible?

Heh.

 

[billyboy999]

First of all, do you want a 'fake' hardware controller or a true hardware controller? TBH, the difference is probably not much for a 4 port device, esp if you are not going to use it intensively. You can get a 4 port 'fake' hardware raid card for 100-150, or a true hardware controller for $200+. If you want an 8 port or higher, there are lots of them out there. Some have SAS ports - one port can support 4 drives.
The easiest way to tell the difference between a fake or true hardware controller is the price, and to look if there's a heatsink or not. If it's got a fan you're looking at a real beast. Honestly.


I second the suggestion that you shouldn't go RAID for your boot or OS drive. It's really not necessary and complicates things. Stick with a normal hard drive or SSD. Use the RAID as a data/games drive. If you really must for performance or data security, IMO this is the only time you should use your motherboard's built in RAID capabilities.
However, RAID5 can do very well in terms of write performance, especially for streaming writes. The only time I would go with RAID10 instead of RAID5 is if performance was an absolute priority.

For hard drives, get cheap and fast. Avoid caviar blacks; they don't play well with raid controllers, plus they're expensive. The ideal drives (IMO) are the 7200RPM deskstars - cheap and fast.

That RAID0+1 scheme you describe wouldn't work because the larger drive would lag behind, slowing down all the 3 smaller drives.