Different HDDs for RAID 0

[reqd]

Picked up a brand new 1.5tb SATA HDD from Seagate and updated my rig.
I have 3 HDDs now, 250gb, 500gb and 1.5tb.
The 250gb has my XP and I don't want to touch it. But, I tried to make a RAID 0 set with the other two hard disks and when I created the set in the BIOS it shows the capacity to be 931gb instead of 2tb(500gb + 1.5tb).... Don't know why. Even XP recognizes it as 931gb.
Any help will be appreciated, thanks.....

 

[tomt4535]

That's normal. Raid 0 really should be used with identical drives. It can only use 500gb of that 1.5tb drive you purchased, as it only goes up to the smallest size drive in the array. That would make the size in windows 1TB. The rest of the space is wasted. If you want to get all 2TB, you can try JBOD, but you wont get the performance increase that you do with RAID 0.

 

[Blazer7]

In addition to that, the overall speed of the array is somewhat constrained by the slowest drive. So, if one disk is faster than the other you won't see any benefits from that extra speed as the controller will try to sync all drives thus "slowing" down the overall performance. In every aspect, using identical drives does matter. Take it from somebody that's running 4 different raid 0 arrays.

*** edit ***

This thread really belongs to the Memory and Storage section

 

[reqd]

thnks guy
I put it on JBOD and got the 2tb I wanted...... I agree I'm missing out on the advantages of RAID 0, but I cant help it. I already purchased a 1.5tb HDD and can't return it, also an array can't be more than 2tb as I have read online. So my only choice is to combine the 500gb and 1.5tb. Still I'm not too keen on the performance increase, I'm cool with just combining the two into a single drive...... Thanks again.

 

[Nothinman]

also an array can't be more than 2tb as I have read online.

That would depend on the controller, every OS out there worth running supports volumes >2TB these days.