RAID 5 controller help

Ok I was looking at a couple RAID 5 controllers and I need some input.

The Fastrack one looks nice with its upgradble memory but I hear it lacks an XOR processor.
http://www.newegg.com/Product/Product.asp?Item=N82E16816102035

Now I am looking at the LSI Logic MegaRaid
http://www.newegg.com/Product/Product.asp?Item=N82E16816118015

What one is better out of the 2 if I was going to use a 3 drive Raid 5 setup now, and expand without data loss later? Also if I am using that controller in a PCI slot can I still use my DFI SATA controller to run my Raptor for the OS?

The fasttrak does indeed lack full XOR capability, so while it can handle some of the load, the processor does most of the work. However, the LSI uses an even older coprocessor to handle the RAID ops, so it tends not to be a whole lot faster, if at all. Both of the boards were reviewed at Tweakers.net some time ago. You'll have to read through their respective manuals to see if they can grow arrays without dropping data - as a word of caution I'd suggest you plan on it not working even if it says it will. There have been too many friends and clients of mine who expected a controller to do this (even if it is a supported feature) and watched as their data went away. Have a contingency plan and a backup of all that data on hand if you try doing this.

Personally I've gotten along better with LSI controllers in the past than Promise, but YMMV. The thing that really turns me off to this particular Promise is the size of the card, though. You can see that it was setup for PATA but converted to SATA to refresh the product line, yet wasn't chopped down to size.

Yes, you can use an add-in controller while still booting the onboard.

K thanks I think I might go with the promise, but i don't know. Thanks for the info about adding disks, i did not know about data loss while doing this.

Your guess is as good as mine with those two units. Aside from some other deciding factor like non-Windows driver support, case size constraints, etc., it's very close.

Just FYI, always plan for data loss. It has the most annoying habit of rearing its head when least expected.

The LSI is a bit faster, but the Promise gets the job done.

The Promise has a known bug where it is very slow with only three drives, but performance is fine with four drives. So if you really want to start out with only three drives go with the LSI board.

Some people have also had problems running the Promise controller alongside an onboard RAID controller, but it seems fine with other non-RAID PATA or SATA controllers.

Both support Online Array Expansion.

The Promise is indeed a large card - it's the bottom one:


Part of the reason the card is so large is because of the SDRAM slot:


With 4x Seagate 200GB 7200.7s, and a 256MB PC133 CL2 ECC module:

The 1820 has no hardware XOR engine and is very slow in writes.

Don't know too much about the 2220, but PCI-X cards should work fine in PCI slots. just make sure that you have room at the end of one of your slots for the overhanging unused connector.

This is a much better controller if you can spare another $20: http://www.newegg.com/Product/Product.asp?Item=N82E16816118011

Go with either one of the LSI controllers (depending on if you need 4 or 6 drives)

I personally built a central file server for a company I use to work for and it worked like a dream. I also own an LSI Express500 for my SCSI RAID5 on my personal workstation at home and it serves me VERY well. (and fast!)

One note though, if you do get the LSI controllers, make sure you pick up the battery pack for it so you can enable WriteBack caching. Without the battery, the card will default to WriteThru for much lower performance. You can force the card to WriteBack but if there is a power failure, you can/will loose data.

This option is usually present on all good qualtiy RAID 5 controllers.

Or just get a UPS like me