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How to upgrade hard drive connection from 3GB/s to 6GB/s?

Is it possible to upgrade a 3GB/s "negotiated link rate" to 6GB/s by installing new hardware (e.g. new controller card)?  For my new desktop I just bought, I was talked into getting an upgraded SAS 15000 rpm hard drive to gain a 6GB/s speeds (model: ST3300657SS NewEgg)  by the Lenovo salesperson.  When I just checked the connection rate, it is only operating at a 3 GB/s speed.  Is there a way I can improve this without returning the computer?  

The computer I purchased is a ThinkStation D30 (M 4354)
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Your PC has two storage controllers - one built-in to the motherboard itself and a separate storage controller card.

Did you plug this new hard drive into the connectors on the motherboard or did you plug it into the controller card?

The storage controller on your motherboard runs at SATA3 speeds (6Gbps) whereas the storage controller only runs at SATA2 speeds (3Gbps) so I think you may have plugged the drive into the storage controller in this instance.
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Dr. Klahn

It's important to remember that when we are talking about 3 Gb/sec and 6 Gb/sec, neither are actually physically realizable by the drive as continuous transfer rates.  6 Gb/sec = 750 MB/sec and there's no hard drive that can flick its heads across the platters fast enough to deliver 750 megabytes per second.  The values quoted are for peak speed, not continuous.

A drive's best performance is transferring an entire cylinder of sectors when the start of the cylinder is coming under the read head just as the request is processed by the drive's controller.  Then it must move the heads and this takes time.  So you can get 6 Gb/sec for one cylinder's worth of data if everything is just exactly right.  After that it takes a few milliseconds to reposition the heads as each cylinder is transferred and the transfer rate drops significantly.
hi mate, mates,

with your config, as other mates said, your hdd is most probably connected to controller that is limited (or configured in bios) to 3Gbps SATA/SAS, but in trully it's not any limit of 15k SAS drive because that drive, even very fast with access speed in comparision to SATA 7k2 drives its still too slow to saturate even 3Gbps link (about 290MB/s), this drive will probably hit close to max 200MB/s so U really dont need more than 3Gbps SAS/SATA link.
If U still wanna to have 6Gbps link check that:
- controller to which U have it connected this 15k SAS drive
- controller settings in BIOS of link speed, that is not limited to 3Gbps
- new controller firmware from vendor (Lenovo or/and controller vendor)
- connection cable that sometimes may be not fully compatible with 6Gbps (it happens really rare but it may happens)
- some jumpers on SAS 15k hdd that limiting drive link to 3Gbps for compatibility
- eventually, irrational to that config in my opinion but U can eventually bought 3Gbps controller or HBA, especially if U plan to get more disks in the future and use hardware RAID 5/6

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The hard drive in question came stock with the system.  I double checked and it is plugged in directly to the motherboard.  Also, there is no hard drive controller card installed that I can see.  I attached a screenshot of my internal system so you can see the hard drives are plugged directly into the motherboard (note I did install an additional 1500 rpm hard drive after it arrived two days ago).

Also attached is a screenshot where I saw that I have a 3GB/s "negotiated rate."  I realize I can't expect a full 6GB/s, but from what I can tell it appears I was sold a "6GB/s setup" that is rated 3GB/s.  The guy at Lenovo specifically went over this me on the 6GB/s.

I guess I just want to make sure I wasn't sold something that doesn't have what I was told it would.  How do I know if my motherboard is rated 6GB/s versus 3GB/s?

ok, I guess that 15k SAS drive is that one connected via rec cable to blue SATA/SAS connector, and that other one connected via black cable You said "1500 rpm" is probably a SATA HDD with rather not 15k RPM but lower like 7k2 or 5kx ??? not looks like SAS hdd also from hw view (dont have additional SAS connection pins like that one higher connected via red cable) and from Intel RAID Storage view where is evidently additional SATA hdd (and one on first plan SAS hdd).

So good U show that controller is C600 SAS RAID, which have up to 8 SAS 3Gbps sockets/ports and 2 SATA 6Gbps ports and 4 SATA 3Gbps ports, which generally mean that it's not a SAS 6Gbps controller at all (SATA 6Gbps is not a SAS 6Gbps, but often SAS 6Gbps is also a SATA 6gbps).

intel C600 RAID hw specs:

So in this situation my 1 solution is to bought another SAS 6Gbps RAID controller, but do it really if U need it for for example more drives with RAID 5 or 6, for other purpose they are (in my opinion useless), until U have some agreement with a someone/customer that it have to work on 6Gbps link.

You need to plug the drive into one of the red SATA ports as those are the 6Gbps ports for your on-board SATA controller on your motherboard. The two orange ports are 3Gbps ports on the same controller.

The four blue ports are for the separate RAID controller which all run at 3Gbps.
"...  6 Gb/sec = 750 MB/sec  ..."  ==>  Actually not true, but nevertheless it's true that no rotating platter drive is going to come close to SATA-3 speed [which is 6Gb/s or 600MB/s, due to the bit encoding/error-correction overhead]

A 15k high-density platter could in fact exceed the 300MB/s SATA-2 rate, but no 15k drive I'm aware of has densities high enough to actually do that [It would require 1TB/platter drives, which simply aren't reliable enough to run at 15k speeds].

The BIG advantage of your 15k drive is the MUCH faster access time -- seek plus latency will be about half of the time of a typical 7200rpm unit ... so you're definitely going to get improved performance with the drive.    I would NOT return it.

You should, however (as noted above), be able to move the cable to one of the 6Gb ports and increase the interface to SATA-III speeds.     That will let your transfers to/from the disk's buffer occur at full interface speed (these are a TINY % of the actual disk activity, so there's not much benefit, but it'll nevertheless be nice to know you're getting max performance).
You're throwing your money away. That disk can't pump data much faster than a 1.5Gbit link.
Actually a 15k drive can easily sustain date rates above 150MB/s ... at least on the outer platters.    I agree, however, that it won't come close to the SATA-2 rate, let alone SATA-3, so there's no real reason to worry about whether it's connected to the 3Gb or 6Gb ports [except for the very tiny % of transfers that are to/from the disk's buffer].

You are talking about SATA 6Gbps (SATA-3) and this drive ST3300657SS is 15k SAS 2.0 (6Gbps) interface drive which is not compatible with SATA interface, it's a SAS drive compatible with SAS 1.0/2.0 standard, so in my opinion it will not work on SATA 6Gbps connector on SAS 6Gbps or SATA 6Gbps speed, and even should not work on SATA port until controller recognize it's SAS drive and switch that port back to SAS (if have such posssibility), but will not switch it to SAS 6Gbps because this controller (intel C600) is SAS 3Gbps compatible (SAS 1.0), not SAS 2.0.

So not make mistakes that SAS drive is compatible with SATA, its not true (until I work with FC, iSCSI, NFS and SAS storages from 10 years), if something changes then ok (it may happens, technology change fast these days :P) but I never heard about such SAS hdd that is compatible with SATA, SAS RAID  Controllers and HBAs are often compatible with SATA (they emulate sata commands) but not in the other way.

Also u can search this Lenovo ThinkStation D30 (M 4354) specs (in attachement) when You have clear info that every default config (without optional LSI RAID 6Gbps controller card) in compatible only with SAS 3Gbps and SATA 6Gbps.

Ok so if I'm understanding what is going on here....  I have a 1500 rpm SAS drive that in no way touches the speed of a SATA 6GB/s drive?  As a result, there is no point asking about the 6GB/s connection as it won't matter either way?  In essense I could have bought a $50 drive with twice the capacity and with faster speed (e.g. SATA Drive) ???  Or is the SAS drive I have competitive to a SATA 6GB/s drive?  Sorry for the confusion here, but I'm beginning to think the Lenovo guy I spoke with had no idea what the hell was going on.
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Gary Case
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Thanks to all for the thoughtful comments... awarding points.