Should NCQ be a factor at all when buying an HDD in a home desktop environment?

Participant · 29 Apr 2007 at 09:57

I'm still struggling to decide between a Seagate 7200.10 and a WD AAKS (2 x 320Gb in RAID) and the only difference I can immediately see is that the AAKS doesn't support NCQ whereas the Seagate does. Obviously there's the noise issue also but I haven't managed to find much info about noise with the AAKS so that doesn't really come into it at the moment.

I have two questions:
- should NCQ be a factor in my immediate decision?
- are there any upcoming developments that may make NCQ an important feature?

Many thanks.

rpstewart · 29 Apr 2007 at 10:45

NCQ and RAID don't mix well at all, if you're RAIDing the drives then NCQ should be turned off. It tries to second guess the RAID controller and sends data in the wrong order so the controller has to retry requests - on a two disk RAID0 array there's about a 15% difference in transfer rates between NCQ off and on.

Participant · 29 Apr 2007 at 11:14

Hmm ok thanks for that.

In that case is there likely to be any change in this RAID / NCQ conflict in the future, or should I disregard NCQ entirely as a benefit for a 2 disk RAID environment, in your opinion?

Of course there's also the possibility that I may ditch RAID in the future, in which case would NCQ offer any benefits in Windows and games? What I'm thinking is that I want the AAKS being fast and quiet by all accounts, but don't want to discount myself from a potentially positive attribute by ignoring NCQ.

rpstewart · 29 Apr 2007 at 11:25

The current NCQ algorithms are very much skewed towards server type I/O load. In a desktop environment the wait queue rarely gets long enough for NCQ to really make any noticeable performance improvements. This may change in the future but the algorithm is built into the drive so you'd need to replace that to see any difference.

Personally I wouldn't use NCQ or the lack of it as a factor in choosing a drive.