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Build Your Own SATA Hard Drive Switch
Mikey Win writes "ExtremeTech shows us a cool hardware hack that allows multiple operating system to boot without dealing with any tedious BIOS setup changes. How? By building your own SATA hard drive switch. The result? You can expect a longer hard drive life span, power supply load reduction, and partitions protected from becoming overwritten or corrupted."
Hrmph. Call me when the switch in question is tied to a massive, mad scientist-quality switch, clearly labeled in big letters with "LINUX" on one side, "WINDOWS" on the other. It should also make a satisfying mechanical switching noise whenever I pull it. And if you can make lightning crack outside my window every time, that'd be nice, too.
Demanding constant attention will only lead to attention.
It's just a drive power switch. I was expecting the actual SATA connection to be switched not just the power to the various drives.
Do people really think that Grub is that hard or this just another case of because we can.
I would like to see what terrible, terrible things happen when some idiot let loose near your computer decides that the knob on it looks weird and takes it for a spin. In the middle of a kernel compile.
And by terrible things, I mean manslaughter.
The design switches ground (Black) as well, instead of keeping it permanently connected. This means that if you use a non-bridging rotary switch (i.e. it does not short out neigbouring connectors when turning it, but has a short phase where all wires are insulated), you could kill disks when switching under power. This happens when +12V and +5V already (or still) have contact but ground does not. The effect is that -7V (a negative voltage) gets applied from Red to Yellow. Typical electronics have a tolerance of -0.5V on their supply lines and die very fast (miliseconds) if that is exceeded in negative direction.
The same can happen if your (bridging) switch gets a bit corroded and does not make perfect contact anymore. This is not so uncommon.
My bottom line is that these people have no clue what they are doing and you should under no circumstances copy this faulty design. If at all, then switch only Red and Yellow, but leave Black
allways connected at all devices. Not only is that safe, there is in fact no sane reason at all to switch Black. I can only conclude that the idea of the designers was to simply switch all wires, without any understanding of the consequences.
I think this solution is also overdone. I have XP and several Linuxes on a GRUB multi-boot on two computers. True, once or twice per year I need to use a KNOPPIX CD or memory stick to boot my system and reinstall the boot manager. Takes about 5 minutes each time. Not an issue at all.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
In fact switching the ground wires under power gives you a high risk of blowing up your drives: If you use a non-bridging switch (or it does not make perfect contact, as cheper ones may do after some time), you can have a situation where +5V and +12V have contact, but ground does not. This typically leads to immediate death of the whole drive electronics.
These people have no clue what they are doing.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.