Hanno's blog

Recently, my old harddisk produced some errors. As I care for my data, I immediately replaced it and decided to invest in an SSD.

My laptop (Lenovo Thinkpad T61) is already some years old, so I'm quite aware that I won't get the best possible performance out of it. But I found something really interesting. The BIOS seems to limit the SATA II speed and there's an unofficial BIOS mod to remove that limitation. It's also available for a couple of other Thinkpad models (beside T61 also for R61, X61, X300 and variants of them).

The BIOS mod also does a number of other things, for example the official BIOS has a whitelist of allowed wireless chips. That gets removed.

The full feature list from the readme file:
- Disabled whitelist check.
- Enabled SATA II full speed.
- Added SLIC 2.1 table.
- Removed "Thermal sensing error" boot message (Penryn CPUs).
- Added dual-IDA support.

Obivous Warning: You're doing this at your own risk. If any unofficial BIOS destroys your laptop or your data, that's bad luck. The only thing I can tell is that I didn't experience any problems and that so far, a lot of people seem to use these BIOS mods without problems.

Now I did some before-after-benchmarking. I used hdparm -tT /dev/sda and a simple dd if=/dev/zero of=/tmp/out.img bs=8k count=256k. I started the benchmark after a fresh boot without anything else running to avoid disturbances. I ran the tests a couple of times and will only give you the last result of each tests, but they didn't differ much. The results:

	before	after
hdparm cached read	3069.01 MB/s	6900.56 MB/s
hdparm buffered read	131.38 MB/s	251.79 MB/s
dd write	106 MB/s	209 MB/s

Quite impressive, isn't it? I just doubled the speed of my disk for free. I'm aware that benchmarking is a tricky business and the impact this has on my overall system performance is probably difficult to put in numbers, but the results are significant enough that I think it was worth it.

Slightly related: There's also a modified firmware for the Optiarc AD7910A CD/DVD burner that's shipped in my laptop.

I have a magnet plate hanging over my desk. Usually, the normal magnets for that purpose you can buy in shops are of very low quality and not very strong and fail to hold more than a few pieces of paper.

I recently discovered a way to get much better magnets almost for free: From old harddisks. To open a harddisks, you will usually need some kind of Torx screwdriver. Inside, you will find one or two very strong neodym magnets, which were originally used to move the read head.

A common way to check the health state of a hard disk is SMART. It gives various informations about occuring errors. In Linux, there's the smartmontools package containing tools to read SMART data of hard drives (smartctl -a /dev/[hddevice] gives you a bunch of information).

I found it always frustrating that SMART didn't work with USB drives. It's a standard bound to IDE/ATA. Although common USB-drives are internally IDE/SATA, sending the SMART commands to the drive requires proprietary extensions. But now, the smartmontools-developers have included support for some USB drives. It worked with the USB HDs I had available for testing.

There's no release yet containing the USB-support. If you're on Gentoo, you can fetch a live-CVS ebuild here.