General information
SATA/SAS crossed or not crossed ... ?
that is the question. Fact is, that the SATA cable must be crossed on its way from the controller to the hard drive, like a network crossover patch cable. However this crossing must be done within the hard drive as of the SATA specification, so that the complete cable must be 1:1. Unfortunately backplanes and slot adapters are provided that already are crossed. It is importand that you then use crossed cables. Cables are mostly named crossed or 1:1 but backplanes and adapters are not.
Two SATA connectors on SAS removable racks and backplanes
The second connector is colour-coded (mostly yellow or orange). It is used to connect a hard drive to a second host controller. When the first controller fails, the second one is still able to access the hard drive (redundancy). Simultaneous access is also possible. But this is only possible with SAS hard drives. With SATA hard drives the second connector is without function.
My external case suddenly is being recognized erroneously by Windows.
Before you send your case for repair, please try following: Connect the external case to the PC. It will of course not be recognized. Now go to the device manager and deinstall the faulty device. Now disconnect the case from the PC and reconnect it.

Background information: We consitently receive external cases which are completely OK. If we would then change the printed circuit board, Windows thinks that a complete new device has been connected and will install a new driver for exactly this device. Exactly the same you accomplish by the above procedure.
Software-RAID over external cases
To create a software RAID on Windows machines you have to convert the accordings HDDs into dynamic volumes. However, Windows does not support dynamic volumes on changeable media (also USB and Firewire). Creating a software RAID over external cases on Windows is therefore impossible.
Formatting hard drives on Windows 2000/XP
Formatting (external) hard drives under Windows 2000 and Windows XP may be impossible when partition is larger then 32GB and filesystem is FAT32; formatting will not be finished. This bug is specific for these operating systems. Perhaps some tools can help (e.g. Partition Magic). Both OSes can access FAT32 partitions properly, this problem occures only when trying to format.

On http://www.ridgecrop.demon.co.uk/fat32format.htm you can find a DOS based alternative tool which works fine.
LG GSA-4120B
This device sometimes causes different errors, when assembled into an external case. The errors are very various and reach from simple non-recognition, problems on burning CDs to System crash. The errors do not depend on the external case, the manufacturer or used chipset of external case. Some cases can be made compatible by a firmware update.

Addendum: Meanwhile LG has improved their devices. This error does not occur with newer drives.
External Cases and Linux
Though not mentioned, our external cases work with Linux. Make sure you have at least Kernel 2.4.20.
Hot-Swap
Hot Swap is the ability of a device (e.g. Hard Drive, Power Supply) to be connected to a computer while computer is running. Hot Swap refers also to disconnection of this device. For disconnection the device sometimes has to be deactivated/unmounted from operating system.
ATX / BTX / EPS / SSI / ATX12V / AMD / WTX ???

ATX power supplies can be recognized by the 20 pin Main board plug. Beside the 4 pin processor power connection another 6 pin AUX connector can be present on 250W and 300W power supplies.

EPS and SSI describe the same by usual linguistic usage, although this, strictly, is not correct. EPS describes only the power supply (EPS = Enhanced Power Supply) and SSI the organisation (SSI = Server System Infrastructure) that standardizes specifications for serverboards and other components. SSI requires an EPS power supply for server boards. The characteristic of the EPS power supplies is that processor mains (8 pin connector) is produced by its own transducer in the power supply in order to increase the stability of processor current. Otherwise the stability of the system could be impaired under load by current and/or voltage fluctuations. Many vendors specify their power supplies as EPS because of its connector, though the other specifications do not come up the requirements named by SSI.

Addendum: The specification allows under certain circumstances that CPU power may be taken from the common 12V line.

Generally an ATX12V power supply is a power supply with processor power connector (4-pin).

In current ATX specification ATX V2.2 the 20 pin ATX connector was extended by 4 pins and corresponds now to the SSI power connector. The processor power connection remains with 4 pins. Besides the SATA HDD power connector was taken up to the specification as well. CPU power is taken from the common 12V line.

AMD has developed his own power connector for some server boards (likewise 24 pins with 8pin processor power connection). The allocation differs from the SSI connector clearly. This connection did not become generally accepted however and meanwhile is no longer manufactured. There are however still mainboards in circulation, which need this connection.

Same as the WTX connection, which was intentionally designed for server boards (Intel?).

The BTX Main Boards need a power supply with 24 pin connector with ATX2.2-Spezifikation. However The design of the BTX power supplies is not compatible with the ATX power supplies.

Mainboards with dual core support may have a 8 pin connector for processor power. The connectors then are the sames as in SSI specification for serverboards. The maximum current and efficiency may be lower than in SSI specification, esp. with cheap power supplies. But on normal use, this will not affect performance and safety adversely.

 
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