How do I get SATA II speed from a P-7805u?

My hard disk died the other day. All my data was backed up, but I could not recover the operating system so I bought a copy of Win 7 Home Premium to load on the new 750GB WD Scorpio Black drive.

The drive is rated 3Gb/s. I d/l the Intel ICH9M-E/M SATA AHCI controller, which shows up in device manager under "IDE ATA/ATAPI controllers" with no errors detected. AHCI is enabled in the registry. The Intel Rapid Storage Technology application that came with the controller reports the SATA data transfer rate is 3Gb/s.

However, I'm only seeing 100 to 150 MB/s sequential transfer rate (exact value depending on the specific software). That's SATA I speed, not SATA II. I should be seeing something closer to 250-300 MB/s. Setting the Power Plan to high performance makes no difference.

The BIOS version is 9C.11.00, if that makes a difference. AHCI is turned on in BIOS too.

Does anyone have any idea what's going on here or what I'm doing wrong?

 

First off when you formatted your HDD was it in AHCI format or no? Otherwise you will have to do reformat to gain usage of AHCI format and it capabilities. But if you have it turned on will in part depend of the chipset if it does have sata II ability to use it.

That there is part of the problem unless you format in AHCI format you won't be able to use AHCI drivers correctly.

 

The bus is rated at 3GBs your drive however can not flood the bus as it is not fast enough. The HDD just is not that fast. You would need one of the newer, and also sata III, ssd drives that actually will support 3GBs. Even then with overhead you never see actual 3GBs........................

 

Ummm, guys. A few points here:

1. AHCI has nothing to do with the format -- it's the controller mode. The controller was already set to AHCI mode when the OS was installed. You are getting confused with boot drive issues when Windows is set to IDE mode and the controller is set to AHCI or vice-versa. It was more of an issue with XP (which did not natively support AHCI)-- since Vista, Windows will auto detect the mode when starting the install and will use the appropriate driver. If it doesn't, there's a simple registry edit to swap back and forth. Given that I can boot from the disk with the controller in AHCI mode, I think it's safe to assume Windows loaded the right driver, but I checked the registry to make damn sure.

2. I realize that drive manufacturers are like used car salesmen, and the advertised 3Gb/s rate refers to the burst rate between the cache and the drive controller. However, this is a nice shiny new WD Scorpio Black. The fine print says 7200rpm, 16MB of cache and 180 MB/s sustained transfer rate from the 3 platters. I should be seeing 150 minimum, not 150 max. (on sustained reads, random access is another matter!)

 

Dude, 180 MBs is the max sustained from the outside tracks of the platters. as you get to the inside tracks this will slow down. This is a limitation of the mechanical design. You need to research this further and if you do not still believe it others all over the net post their benchmarks as well, compare them!

Again if you want true SATA II speed over the bus get a SSD. You then eliminate the mechanical limitations and are subject to the electronic weak link. Not all SSD's can even flood the SATA II bus though so select your drive carefully.

ACHI supports extended SATA commands not speed. The format is mainly for commands that wil support enhanced SSD needs and, not too sure about this one, advanced format etc.

 

Like this one?

Western Digital's Scorpio Black 750GB notebook hard drive - The Tech Report - Page 3

Burst read speeds of >180, burst write >190. I'm getting burst speeds of 145 - 151 using the same software. Now, that's burst speed, not sustained write speed. I don't know why they didn't benchmark that.

You are probably correct in that there is a difference in the media transfer rate from the inside of the platter to the outside. (I would think it to be even more dramatic with WD's "Advanced Format", which is supposed to be the magic that squeezes extra data onto the 750). And of course, WD is only going to advertise the maximum. That likely explains the wavering sustained rate (ie: 100 - 150) that I am seeing.

There's no way on God's green earth that this 2-1/2" mechanical drive will ever be as fast as a SSD. But I still don't think it's the only bottleneck here.

 

it is the bottleneck. 2.5 Mechanical drives just are not fast enough to saturate Sata II and just recently on the outer tracks comes close to saturating SATA I. Just the nature of the beast..............

 

Since you didn't specify what kinda O/S all this talk is meaningless without even knowing what O/S your running. The AHCI controller and software gets installed when that feature is available but again without knowing what O/S your running that again is a mute point of discussion.

Advanced Host Controller Interface - Wikipedia, the free encyclopedia

 

My second sentence in my opening post:

Booting with the controller in AHCI mode is not the issue. I'm just trying to establish if the connection is SATA or SATA II. To me, it seems that the speed is being clipped at 150MB/s, despite the SATA II-capable chipset and Intel Rapid Storage Technology application. TANWare thinks the drive just isn't capable of crossing the threshold, and he might be right. I guess the only way to know for sure is to connect a SSD to the e-SATA port and see what happens.

 

I wonder if 7811 and 7805 are the same. I put a SATA 2 SSD in my 7811 and it reads average 175MB/s in HDTune. No speed record but pleasant in real world use. I thought it would do better. All drivers current and AHCI. I'm not sure what else to try.

I wonder if programs like HWInfo report the SATA revision if it reads the drive controller or the bus? I would guess the drive controller.

 

It is SATA II with these. My SF2 SSD with compressible data will do 285 MBs. The bus will transfer at this rate easily but the drive itself is limited. Whit compressible data the drive handles these speeds but when the data can not be compressed the drive cant read or write data that fast...............

 

Is yours the 7805 or the 7811? Which BIOS are you using?

 

It was a P7805, the P7811 shares the same chipset. the PM45 raid capable chipset supports SATA II etc so there is no difference in that aspect of the machines. Now my machine is a P79xx...................