rdkapp

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I just built my 2nd system. My 1st recently died from bad caps on the mobo. Anyway, I've got a minor issue about which cable(s) to use for my SATA hard drive. I've got the following choices:

1. Straight SATA data cable with a SATA power cable from my PSU.

2. SATA cable with a large combined power and data connector for the hard drive.

#2 is what was being used in my 1st build and to my knowledge, I never had problems. Obviously, in the case of #2, the power for the hard drive comes directly from the SATA port on the mobo as opposed to directly from the PSU in #1.

#2 seems to result in a little less cable clutter and thus, may be better for airflow, but I wonder about the power. Does the SATA port on the mobo carry the same power as the SATA molex connectors that come directly from the PSU?

I guess the bottom line is: which is the preferred method of cabling for a SATA hard drive?
 
There are no power pins inside a desktops mobo's SATA ports.

http://www.allpinouts.org/index.php/Serial_ATA_(SATA,_Serial_Advanced_Technology_Attachment)

So I'm really not sure what you are talking about. For any disk drive, the data cable's source is the mobo port, the power cable's source is the psu. At the disk end, there may be a combined connector, as for 2.5" HDs.

But power and data are separate at their sources. We use separate cables because they come from different directions, and there's no need to add an adapter at the disk end - just another point of contact to give a problem.
 

rdkapp

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There are no power pins inside a desktops mobo's SATA ports.

http://www.allpinouts.org/index.ph [...] ttachment)

So I'm really not sure what you are talking about. For any disk drive, the data cable's source is the mobo port, the power cable's source is the psu. At the disk end, there may be a combined connector, as for 2.5" HDs.

But power and data are separate at their sources. We use separate cables because they come from different directions, and there's no need to add an adapter at the disk end - just another point of contact to give a problem.
Thanks for the reply Twoboxer.

To clarify what I am talking about in #2 of my initial post, see the following photo.

dsc01766a.jpg


The large end connects to the hard drive while the small end connects to the SATA port on the mobo. I had no other power source connected to the hard drives. So, my question still stands.
 

rdkapp

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With no replies, I guess we're not learning much. :(

Just wanted to update the thread with some additional info (nothing earth shattering) and what I decided to use.

I asked the tech support guys in the local Micro Center and they were familiar with the cable, but said they hadn't seen one in a while. They said that SATA works similar to USB and can power some peripherals to an extent, but with hard drives, they said they could see it with a 2.5" smaller capacity HD, but not 3.5" large capacity drives like mine. They said the DFI board may have been set up to send more power to the SATA ports, but they were unable to support that with data from the DFI site. Finally, they said there was a possibility that powering the hard drive(s) that way may have contributed to the caps going bad on the DFI mobo, but that was speculation.

Anyway, I decided to go with the SATA power connectors from the PSU and the SATA data cables with the small connectors that came with the Gigabyte mobo. I figured that newer cables would be compatible with any newer SATA standard and I also liked latches on the connectors.
 
Good move lol. I'd never seen a cable such as the one you posted. And I'll tell you I never would have believed you without the picture lol.

Cables *similar* to that *are* used for 2.5" drives (where the power/data connectors are really jammed in together). But the other end of the cable is split in two so it can grab power (which it sends to the power part of the HD connector) and data (which it sends to the data part).

As you've seen, the standard pinout for a SATA data cable connector does not provide for any power pins. There are 7 pins, 3 ground pins so they can surround/separate the pair of TX and pair of Rx pins. If DFI used one of those pins for power, it would be horribly non-standard lol.

Anyhow, hold onto that cable :) And enjoy your rig.
 

rdkapp

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Thanks Twoboxer. I have seen the cable you described also. It has a female molex on the other end, so it is obvious where the power is coming from there. Back when I built my 1st rig with the DFI mobo, SATA was fairly new, and the PSU that came with my case (that has since died) had no SATA power connectors. Plus, I didn't know crap from crapola when it came to powering the SATA drives, so I never really thought about it. I just put it together and it worked. Then, when I got a new PSU (2 - 3 years ago), it had those strange looking (SATA) connectors that I just left alone, since everything (but the PSU) was running fine.
 

rdkapp

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Oh, I'm having some fun :bounce: and beating my head against the wall at the same time. [:bilbat:3]

I wasn't sure if I needed to make a new thread or not, so if I do, please let me know.

I have Windows XP Professional, and I'm looking into the issue of AHCI / SATA vs. Native IDE and I must say that I am a bit confused. My BIOS shows that my SATA Controller is Enabled and the SATA type is Native IDE. When I switch it to AHCI, the system won't boot. When I switch the BIOS setting back to Native IDE then XP loads successfully.

My research tells me that AHCI is necessary for hot swapping and something called NCQ (Native Command Queuing). I'm not sure that I would benefit from either one of those features, but if I would, I certainly want to use AHCI. I am running a desktop, but do have a home network and I, as well as others in my home network, do access my drives on occasion, but it's nothing like in a work server environment.

Here's my question and perhaps it's just a matter of semantics, but having my SATA drives, that supposedly have superior performance to IDE drives, set to "Native IDE" leads me to believe (perhaps incorrectly) that I may not be getting full SATA performance from them. For example, my boot drive is a 250 Gb 3.0 Gb/sec WD HD. With a "Native IDE" setting in the BIOS, will I be getting the 3.0 Gb/sec performance?

There's also the consideration that even though I won't benefit from it now, what about the future? You never know what the future may bring, right? So, unless I'm told with conviction, that I don't need it and shouldn't activate it, I believe I want AHCI.

So, now the question is, how do I get AHCI? I think I understand that in order to properly activate AHCI, I need to make a driver disk by retrieving the driver from either the mobo driver CD or the AMD website and install the driver during the beginning of the XP installation when presented with the F6 option. Please correct me if I am wrong, or if there is a way of doing it after XP installation is complete. Apparently, it doesn't work by installing the drivers from the mobo driver CD after XP installation, which is what I did initially.

I would appreciate any light that can be shed for me on these issues:

1. Do I need AHCI, either now or in the future?
2. Whether I need it or not, is there any way to activate it / load the driver after XP installation is complete?
 

rdkapp

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OK, I think I found the answer to the above. I believe the answer lies in the FAQ sticky thread at the top of this sub-forum, here: FAQ sticky. For the current state of my system (only OS and mobo drivers loaded), that seems to be more involved that just reloading the OS using F6 with the AHCI / SATA drivers on a floppy, which I'm planning to do later on today. In the meantime, I am still interested in some feedback on the other part of my post; i.e. will one get full SATA performance from a SATA drive with the controller set to Native IDE?
 
Frankly, as long as you are using XP I wouldn't bother. You aren't hot swapping, and aren't likely to. And the HD performance will be the same.

If you decide to use an SSD as a boot drive, you are going to want to move to Windows 7 anyhow. So AHCI decisions can safely be deferred until that point.