mthomas99

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Ok looking at either a 200gb SATA 150 West Digital HDD or a 250gb SATA 3.0gb/s West Digital HDD--

Gona use a ASUS A8N-Sli Premium MOBO which suuports sata 3.0gb/s it says in manual--

will there be much of a difference? will i have to some how tell the mobo to change the speed to 3.0gb/s or will it automatically recognize the 3.0gb/s speed if i buy and plug int he 250GB SATA 3.0gb/s hard disk drive?
 

fishmahn

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No difference whatsoever... well, maybe a couple points in burst speed, but nothing you could notice except in a benchmark. No hard drive can get close to 150mbps that SATA'1' has, so SATA2's 300 is all marketing hype.

Mike.
 

moboking

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The bottleneck here is not the interface but the rotational spped. This is why all modern SCSI drives spin at 10,000rpm. Some even do it at 15,000. Therefore if you want speed, there are SATA1 drives that spins at 10,000rpm.

The reason we have a change in the interface as opposed to a change in the rotational spped of IDE drive is cost. It is more expensive to increase the rpm than changing the interface. Another issue is power consumption. SATA drives consume less power. However it is not to say that SATA1 drives spinning at 7,200 rpm is the same speed as IDE. The SATA is still faster, but's it's not fast enough to brag about until that SATA drive increase the rpm. NCQ also helps as well by not increasing the bandwidth, but making it more efficent with do more per movement of the readhead.

I deally at this point if you want speed, get a drive that is rated as SATA2.5. Any SATA2.5 drive is both 3Gb/s and NCQ. Then make sure that the SATA controller is also 2.5 compliant.
 

nobly

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Ok looking at either a 200gb SATA 150 West Digital HDD or a 250gb SATA 3.0gb/s West Digital HDD--

Gona use a ASUS A8N-Sli Premium MOBO which suuports sata 3.0gb/s it says in manual--

will there be much of a difference? will i have to some how tell the mobo to change the speed to 3.0gb/s or will it automatically recognize the 3.0gb/s speed if i buy and plug int he 250GB SATA 3.0gb/s hard disk drive?

It won't make any difference at all. The only way SATA and SATA 2.0/2.5 will make a difference is when you are running a RAID system.
After 2 SATA drives in a RAID 0 system, you will begin to approach the SATA 150 theoretical limit.

Read this for more info:
http://www.seagate.com/docs/pdf/whitepaper/TP-539.pdf
 

moboking

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The White Paper confirms what I have been saying. The bottleneck here is the mechanical aspect of the drive, not the interface. Therefore, you have 2 options to increase the data transfer: get one drive that spins at 10,000rpm or two or more drives at 7200rpm and put them in a RAID 0. Or both if you want.

I am not clear on the relationship between RAID 0 and SATA Port Multiplier. If anyone has some online info on this, please post it. They both seem to behave the same to saturate the bus speed of 1.5 or 3 Gbit/sec to reach the practical limit of 250MB/sec.
 

nobly

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The White Paper confirms what I have been saying. The bottleneck here is the mechanical aspect of the drive, not the interface. Therefore, you have 2 options to increase the data transfer: get one drive that spins at 10,000rpm or two or more drives at 7200rpm and put them in a RAID 0. Or both if you want.

I am not clear on the relationship between RAID 0 and SATA Port Multiplier. If anyone has some online info on this, please post it. They both seem to behave the same to saturate the bus speed of 1.5 or 3 Gbit/sec to reach the practical limit of 250MB/sec.

Yes, the mechanical part of the HDD is the bottleneck. However, increasing the rotational speed of the HDD causes some issues to arise: 1) temperature increases, hence the need for active fan cooling for raptor drives, 2) shorter life span of the drive.

Next year (I think) the latest advance will come - perpendicular recording. This will help alot in the performance sector and I think we'll actually start to see some actual real life increases.

As for the Port Multiplier, just because a motherboard has 4 SATA ports, doesn't necessarily mean that it supports 150MB/s on each one. I think the port multiplier here means 1 SATA channel, but which is split between 4 drives, in the case of the white paper. The RAID 0 in the white paper is saying that when 4 drives are run in RAID 0, then the single SATA 3.0Gb/s channel is starting to become saturated, since each drive is 60MB/s, for 240MB/s. 1.5Gb/s is really 187.5MB/s. So we can see that 4 RAID 0's on SATA 150MB/s is overwhelmed at that point.
 

moboking

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Now that we have single core CPU that approaches 4 GHz and dual core at 3.2 GHz per core with quad core coming soon, coupled with RAM running at 677MHZ dual channels, at this point, the bottleneck is the hard drive. I think with more and more people use their PC for multimedia including PVR, drive and motherboard manufacturers should pay more attention to the bandwidth of the harddrives. I have a RAID 0 with 2 SATA 150 drives in my system and it's still not fast enough when transfering video files. When I can find both drives and controllers that are certified as SATA 2.5, I will upgrade for sure.
 

RichPLS

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I just bought an Opteron 175, Asus A8R-MVP 4/ports SATA 2.5 with 2x - 74gig Raptors to be set up in RAID 0, then I have SATA2.5 - 2x WD 250gigs for RAID1 data drive.
Coupled with that is a HiS X1800XT.
Rest of parts should arrive tomorrow!
 

nobly

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I thought SATA was 150mbps per port, not /4ports, so if you have 4 drives accessing simoultaniously, that each has only a 37.5mbps bandwidth to operate...

ftp://download.intel.com/design/motherbd/bx/D3611001US.pdf
Look at page 28 where it details what SATA chip this board uses.
"As a manufacturing option, the board provides a Silicon Image Sil 3114 Serial ATA (SATA)
controller and four connectors (that support one device per connector) for SATA devices. These connectors are in addition to the four SATA connectors of the ICH7-R/ICH7-DH SATA interface.
The Sil 3114 controller uses the PCI bus for data transfer and provides a maximum data transfer rate of up to 1.5 Gbits/sec."

The controller uses the PCI bus for data transfer, and that gives you 150MB/s bandwidth. Therefore, there are 4 ports on this channel of SATA. So SATA is 150MB/s per SATA Channel, not per port. Every channel can have multiple ports. That is the reason there is a MUX (or multiplexer) in the Seagate white paper. This also makes sense, because no HDD available today that I know of has a burst rate of 150MB/s. Most are in the 50MB/s-80MB/s range. Its a waste, unless you combine 2 or more HDD's in a RAID system.

Even if you had 4 drives on a RAID 0 system on SATA 150MB/s, it would still outperform a single drive since you max out the bandwidth on the SATA bus.

They can tack it on to the PCI bus because the PCI bus runs at 266MB/s these days - depends on the board's clock, 33Mhz or 66Mhz.

P.S. Thats a sweet system!