Quote Originally Posted by 6_6_6 View Post
Hello Folks,

I have Samsung 500GB Sata drive. It is 2-3 months old. I cannot get NCQ working properly on this drive. I do have many NCQ drives but they are old and this is the only one with the newer NCQ support as advertised by Samsung. Hence I cannot test other NCQ drives.

I upgraded my system of 6-7 years 3.0 GHz P4 recently and I do not see any performance difference in anything. I thought NCQ is likely to make a difference in multitasking. I can't believe they could not get this right since 5 years.

Problem is... Whenever I do any simultaneous disk operations, my system comes to a screeching halt. For example, if i do an md5sum operation, or winzip, 3dmark opens in 3 minutes! Everything fine with the disk. I can hit 90 mbps in single operations. But as soon as I need something else to access the disk, performance degrades beyond belief.

For example, HD_Speed, single instance I get 90 mbps... As soon as I open a second copy of the program and run it, both instances drop down to 10 mbps for a total of 20 mbps speed (as can be seen in Windows Disk Monitor from taskbar). I get the same performance without AHCI in the same machine.

Gigabyte X380-DQ6 F7 (Tested with few other bioses as well)
Q6600 @ 3.0 GHz
2 GB DDR-1066
Gigabyte 8600 GT
Silentmaxx 500W PSU
Zalman Reserator XT (pump insulated to eliminate noise)
No fans. CPU, GPU, HD, PSU watercooled.

2008 Server Enterprise x64

Tested with clean installs of 2008 Server x64, 2003 Server x64, Vista 32 with no change in results.

So could someone check their drives and see if NCQ is performing well on this mobo? Please have a look: http://forums.storagereview.net/inde...howtopic=26006

Is it my hard disk that does not function as advertised?

Thank you!

Maria
Well, that problem is also OS-related. A typical desktop-OS has its schedualer tuned to give userspace applications priority,- and in most cases, one application needs the most juice at any time. There are ways to change settings in the way NTkernel does schedualing and prioritizing, but in most cases, the default configuration will prove the most sound for a typical desktop environment.

Apart from that, you will be able to get alot more performance if the disk-intensive processes do their work on different harddrives. Keep in mind that the a harddrive can only do one thing at a time. When you ask it to read/write at the beginning of the plate, AND the end of the plate every other time, things are going to take longer to complete. NCQ or no NCQ, multiple processes running diskoperations on the same drive is and will allways be slow using a harddisk drive.