Large Decrese In Performance With Better Adapter ? in Hard Disk Drives (HDD) Posted February 11, 2004 · Report reply Is there any reason why changing to this seemingly better controller could cause nearly a halving in the perfomance or am I being blinded by untrue benchmarks ? I agree generally with Pradeep here, though I do have very solid Adaptec RAIDs with good performance. However, I think that it is worthwhile to point out that you should not assume RAID=Better performance. RAID processing requires some overhead, and you are only going to get better performance - offsetting that overhead - if the adapter compensates for the overhead and the disk configuration is intrinsically superior to the non-RAID comparison. Look carefully at RAID performance ads - usually they are over 10 spindles, often maxed out at 16 or 32 spindles. Two drives is barely a RAID. Your desire for redundancy is good, but it is doubtful that you will get an overall noticable performance boost, though you might be able to measure the difference on benchmarks. Most RAID controllers are optimized for conservative data protection with many many spindles. It is very common for me to hear from clients that they are disappointed with RAID performance. Of course, they have invariably bought 3 74G drives for their RAID instead of 9 18G drives. Right now you'd be better off returning the RAID controller and using the $ to install a Raptor for your OS drive. Make the SCSI drives data drives.