Does Raid 0 reduce the amount of HDD space you have with 2 drives?

[Foolios]

I could have sworn I had two 250GB drives installed as RAID0. I thought that by choosing this that the striping would be split across the drives. So unlike RAID1 which would make 2 drives become the size of one I thought that RAID0 would keep the actual size of two drives. For example 2 250GB drives should = 500GB. But upon further examination I realize now that I don't have access to 500GB but am only able to use 250GB.
Can someone give me a little more info on this? Maybe somehow I accidentally put in 2 125GB drives? That's my guess at the moment without cracking the case open...

Thanks in advance.

 

[Automata]

With 2x250 gig drives



RAID0 = 500gigs total

RAID1 = 250gigs total

 

[Foolios]

THank you. I must have put in smaller drives than I thought. Thanks for verifying the sizes.