3HD Raid5 best practice for an extra scratch drive?

[bloort]

i have a 3 disk nvidia 590 raid 5 sata2, and i'm quite happy with it.

I'm going to add a 4th drive just as a scratch drive for temporary files, hoping it's going to make the performance of the raid, lets say, smoother?

My question is, when i add the drive, the bios gives me the option to have the bios itself, or the raid controller manage the drive.

Please correct me if i'm wrong, but wouldn't having the bios manage the single platter, and the raid controller manage raid result in the best peformance.

thanks in advance for any insight and knowledge. and thanks tom.. this has been a great website.

peace.

 

[NetworkStorageTips]

If you are not going to add the 4th drive to the RAID array I would not hook it up to the RAID controller.

In fact, most? RAID controllers REQUIRE you to put the drive in an array of some type to even access it.

No point in doing that if I understand your purpose in adding the 4th drive.

 

[bloort]

My Bad. I meant system bios, as this is a chipset sata raid, not a dedicated controller card. I've added the fourth drive now, and set the system bios to manage the drive. HDtune.com benchmarks show the drive is performing up to speed.

My thinking, which may be wrong, is that there are two settings for the drive in the system bios. system controlled, or raid controlled, (or disable). I'm not sure what would happen if I handed the disk over to the "raid controlled" setting. Would existing data survive? Would I still have a second drive and drive letter? Would I/O operations be more efficient than "system controlled" under heavy loads?

the best thing i guess would be to backup everything and start hacking. this is an nVidia nForce 590 chipset on the motherboard. Performs quite well with sata300 750B barracudas X 3 raid5. HDtune reports around 140M/s and i think around 12ns.

My assumption is that having the 590 chipset manage all the drives would be optimal, but there is little documentation that i can find on the matter. thanks for the reply NST.