Ramblings from another nerd on the grid
One of the questions that has come up from time to time about the ThinkPads is the speed of the SATA interface. Usually the question is about the Ultrabay hard drive adaptor. But more recently this question came up about the T400, W500 and W700 machines. This question is primarily from the Virtualization SME's trying to get every ounce of performance out of their laptops.
After reading an interesting story on the Lenovo Blog - Inside the Box about SSD drives, I decided it was time to run some tests on the W500 sitting in my home office. I have a new eval unit sitting there needing a beating so I decided to hook it up.
For the tests, I ran a bunch of copies to see if I could spot a material difference between the Lenovo ThinkPad T61p and the new W500. For my test harness I used an external SATA 300 eSATA enclosure with a SIIG eSATA ExpressCard. The laptop drive used in all cases was the Hitachi 2.5" 320GB 16MB model HTS723232L9A360. All tests were conducted using Windows Vista Enterprise x64 and Windows Server 2008 Enterprise x64 using the SIIG Windows Update drivers.
Much to my surprise, there was no material difference in the time it took to copy 39GB of data using the ThinkPad T61p or ThinkPad W500. How would you interpret that? It seems like there are two possibilities. Either the primary drive bay on the T61p is SATA 300 and so is the W500, or the primary drive bay on the W500 is SATA 150.
I asked Matt about this in the comments of the Lenovo blogs SSD Drive article but have not seen an answer yet. In all fairness he might be on vacation and has not had a chance to check. You'll also notice in his article he believes the unit he is testing is also running in SATA 150 mode and there is either a BIOS or driver issue preventing the SSD drive from delivering the full speed. Sure sounds familiar.
So I don't think any definitive conclusion can be drawn from my tests other than both machines accomplished the chores in the same amount of time regardless of direction (internal->external or external->internal), regardless of OS, etc. I'm hoping a driver or BIOS update will change that before I have to turn the W500 eval unit back in.
One thing did floor me in the early tests I later corrected. Initially I was using a Hitachi TravelStar 100GB SATA 150 laptop drive. That drive spins at 7200rpm and has a 8MG memory cache buffer. The copy times improved dramatically when moving to the 320GB drive and assuming it was running in SATA 150 mode, the only difference between the two is the increased 16MB cache buffer. But the copies completed in half the time. That's a pretty big change between the drives. Moral of that story? If you are holding on to 2-3 year old 2.5" 100GB drives, do yourself a favor and move to the newer drives.
Lenovo limited the SATA interface on most of their notebooks to just SATA150 to "save battery life". Even if the interface supported SATA II 3Gbps it is limited to just SATA I 1.5 Gbps. A stupid decision if you ask me. And there is no bios setting to remove the limitation.
For a single drive, it's nowhere near saturating even the SATA 150 interface, except when the data is cached (which wouldn't affect a 39 GB copy test). Or maybe I misunderstood your test....
Keith -- saw your incoming link. I actually don't have an answer yet, but I did ask our team of engineers to try and find an answer. They haven't gotten back to me yet. I hope to have an answer because 1. it's needed ,and 2. because I have a vested interest in it.
Thanks Matt. If you hear back let me know. I have to return my W500 eval unit so I won't be able to test any fixes.
I do however have a whole group of friends over here that just received W500's and will be running Hyper-V virtualization with Windows Server 2008 x64 and Windows 7. They will be very interested in a fix.
And when we ascertain it is fixed, I will certainly update this post with that information.
If I understand your test correctly, the problem comes from your HDD. The max. performance of the HDD will never reach the SATA 150 and hence in both case T61p and W500 will have the same result.
Exactly. A typical, consumer-grade, hard drive will average about 50-75 mb/sec or so... you'd need to stripe a couple drives (raid 0) to approach 150 mb/sec. Stripe about 5 drives to get over 300 mb/sec.
Exactly? By that logic I would not see any difference in using eSATA and USB.
Consumer SSDs are available with speeds of 250MBps. SATA-I performance is not adequate.
Thinkpads advertise SATA II performance, but they don't provide it.
Thinkpad owners are finding their SSD performance cut in half by Lenovo's make-believe SATA II.
This a real problem. Lenovo needs to fix it.
If it's a hardware problem (motherboard), that's going to be a really expensive fix. I hope this is a driver or BIOS fix for their sake.
Lenovo has issued an official statement.
Certain Thinkpads advertised as SATA300 are actually limited to SATA150. But Lenovo does not plan to fix the issue. Meanwhile they continue to advertise SATA300 support for the affected models.