Question about using Mismatched Drives for RAID

[Havokator]

Is there any reason why I shouldn't run 3 2TB drives that are from different manufacturers in an onboard ICH10R RAID5 array?

All 3 drives are 2TB, one is a WD20EARS and 2 are Samsung Spinpoint F4's.

I know it is best to run all the same exact drives in RAID, but I was wondering why? It seems like you have a higher chance of 2 or more drives failing at the same time if all the drives are from the exact same manufacturer/batch.

[Anvil]

Is there any reason why I shouldn't run 3 2TB drives that are from different manufacturers in an onboard ICH10R RAID5 array?

No, not really

All 3 drives are 2TB, one is a WD20EARS and 2 are Samsung Spinpoint F4's.

I know it is best to run all the same exact drives in RAID, but I was wondering why? It seems like you have a higher chance of 2 or more drives failing at the same time if all the drives are from the exact same manufacturer/batch.

The WD will most likely drop out of the array, WD changed TLER some time ago on those drives.
So, unless you've got an old WD20 it could cause problems.

There are a lot of theories about picking drives from different batches and so on but the simple answer is that you will not be safe, eventually they will fail.
If they all are from a "bad" batch they all might fail "within days" of each other. (worst case scenario)

Anyways, raid is not backup.

[BrightCandle]

You'll see a reduction in performance compared to if they are matched perfectly.

With 2 drives in Raid 0 you expect a 2x performance boost in read speeds and in IOs. I've tested a VelicoRaptor and a Raptor (both WD drives) and the performance was 1.1x the VelicoRaptor in some cases and 0.5x (ie slower) in others.

Test the performance and make sure the mismatch isn't costing you too much before you call it job done.

[Computurd]

I used a mismatch raid 0 with spinners for years...worked great