Tom's Hardware > Forum > CPU & Components > Other Components > what is NCQ??

what is NCQ??

Forum CPU & Components : Other Components - what is NCQ??

Tom's Hardware: Over 1.4 million members in 6 different countries available to answer all your high-tech questions. Sign up now! Its free!

Bottom Search this thread

hi there. what exactly is the NCQ(native command queuing) in a hard drive??does it need special drivers or something?can someone activate it or deactivate it??

thanks

It can be deactivated (either the BIS and/or driver/XP setting, I can't recall which), which is recommended for most users in all but the most intensive server applications, from what I have read....

Reply to mdd1963

Native Command Queuing. The ability to queue i/o requests and reorder them to allow the hard drive to be its most efficient. No need to disable. It is a good thing.

SATA and SCSI have this ability.

Reply to bjbrock57

NCQ actually takes a performance hit if using RAID on workstations/home PC's, but correct, whether on or off on a single drive does not make a noticable performance difference.

Reply to RichPLS

thanks you guys for your responses.
how exactly can i turn it off and on??actually i have the sata configured as raid in the bios(two raptors in raid 0) and i am wondering if this ncq is going to work at my western digital sataII if i just plug it in to the other sata port. will i need to change ths setting to sata configured as AHCI so as the disk can work as a sata II with the NCQ enabled?or i can just plug this disk to the silicon image??
thanks again for your help!!

my mobo is asus P5WD2 premium

Reply to fiestaria

I don't understand why you'd want to disable NCQ.
It doesn't affect the recording of data, only access times.
The best analogy I've ever heard of what NCQ does is as follows:

You have a restaurant. You drive your truck to a wholesale food warehouse to buy some supplies. You hand a list of items to the warehouse employee, and he gets on a forklift to pick them up. Your list was in no particular order -- you just wrote things down as you thought of them. The employee picks things up in the order that you wrote them down.
That's how an older hard drive without NCQ works.
A hard drive with NCQ is like a warehouse employee who has common sense.
He looks over the list. You want frozen hamburger patties and fish sticks? He goes to the freezer and gets both at one time. Sandwich buns and sweet rolls also on the list? He goes to the section of the warehouse where the breads are stored and picks up both at one time.
In practical usage, what NCQ does is organize the search for data on your hard drive, reducing seek times and possibly reducing wear on the magnetic arm.

Message quoted 1 times

Reply to brainysmurf

Read and see how performance can be increased by disabling NCQ on non-server PC's

http://www.gamepc.com/labs/print_c [...] e%5Ftest=1

Reply to RichPLS

Quote :

One of the Raptor 150's major new features is the ability to support NCQ (Native Command Queuing) technology. NCQ, when active, allows the drive to re-order read/write commands to process them quicker, instead of processing commands in the order in which the drive received them. In theory, this should mean NCQ is faster in just about every scenario, especially during heavy multi-tasking where you're reading data off of different sectors of the hard drive. NCQ, heralded as the "next big thing" for hard drives, is suffering from a backlash of sorts recently. Many users are claiming that you can receive better performance by turning NCQ off.
Sure enough, while running our disk benchmarks, we were confounded that the new Raptor 150 drives were not performing quite as well as expected. Luckily, the Areca 1220 PCIe RAID card we tested with allows you to enable and disable NCQ technology through its software interface, and doing so improved our benchmarks by quite a lot in some cases. Now, we had expected that disabling NCQ would help in some of our benchmark scenarios, but amazingly, nearly all of our benchmarks showed performance improvement with NCQ disabled. Here's a quick breakdown of the performance differences we saw with a four-disk RAID-0 array of Raptor 150 disks with NCQ enabled and disabled.

Reply to RichPLS