This is a list of PS/2 to USB adapters. Information should at least include USB Vendor ID and Product ID, as they are more or less unique for a given controller and thus ideally suited for comparison. (This doesn't mean that adapters with the same ID will always behave the same, as external components may also play a role and the ID can be faked, but it should suffice to point out some general trends.)

Contents
1Getting the information 1.1Windows 1.2Linux 1.3OS X 2Issues you might encounter 3The list

[top]Getting the information

[top]Windows

Information about connected USB devices can be retrieved by using USBDeview.
Look for "USB composite device" in the description column, then select it and click "properties." Most PS/2-to-USB adapters consist of one composite device and two HID devices (the composite device ties both HID devices together); the composite device and its HID devices have the same VendorID and ProductID, so it's irrelevant which one you choose.

Look for VendorID and ProductID. These IDs uniquely define a USB device (or the chipset used), so behaviour should be consistent over different brands if they use the same chipset.

[top]Linux

Code:

bash$ lsusb
[lots of other devices stripped]
Bus 003 Device 010: ID 0a81:0205 Chesen Electronics Corp. PS/2 Keyboard+Mouse
bash$

[top]OS X

Using the GUI, open Applications ▸ Utilities ▸ System Profiler and select USB in the sidebar on the left.

Or, from the command line,

Code:

$ system_profiler SPUSBDataType

[top]Issues you might encounter

Not all USB adapters are perfect. Potential issues to watch out for include:

No ISO layout support - meaning that the 102nd key will not be recognised (badly programmed firmware)
Other unsupported scancodes, like non-functional Alt-PrtScr
Inability to work with boards having a higher current draw, e.g. Model M
Pickiness in terms of pointing devices (jerky mouse, non-working trackpoints)
"PS/2 reset" issues (keyboard won't accept keypresses for a few seconds, LEDs flash)
Slow status LED update

[top]The list

VendorID: 04d9 (Holtek Semiconductor, Inc.)
ProductID: 1400

- Supports ISO layout
- Does not work with Endurapro's Pointing Stick
- Frequent "PS/2 reset" problems (keyboard won't accept keypresses for a few seconds, LEDs flash)

VendorID: 13ba
ProductID: 0017

- Does not support ISO Layout
- Mouse somewhat jerky
- Supports Model M
- Does not support second keyboard in mouse port
- Protocol issue; when holding down a key, then hitting another key, the first key is no longer sent

VendorID: 0d3d (Cypress Semiconductor - note: SW incorrectly reports Tangtop Technology)
ProductID: 0001

- Supports ISO layout and 104/105 key keyboards
- Works with boards having a higher current draw, e.g. Model M
- No mouse or trackball support
- Windows, Mac, Linux users report as being compatible
- Not compatible with SGI Granite 9500900 (but then again not sure if any are)
- Recommended by ClickyKeyboards
- Commonly referred to on forums as "Blue Cube"
- Manual here

VendorID: 0b39 (Omnidirectional Control Technology, Inc.)
ProductID: 0001

- Works with Model Ms and Model F AT
- Works with CH Trackball
- Works mainly with SGI granite except Pause key not recognized

VendorID: 05f3 (PI Engineering, Inc.)
ProductID: 0203
PI Industries Y-Mouse

- Works with 1990 1391401.
- Claims to support two keyboards, two mice, or one-of-each.
- Programmable -- stores some key-mapping settings internally (i. e. right-alt to Windows logo)

VendorID: 0711 (Magic Control Technology Corp.)
ProductID: 0240
Lindy USB PS/2 adaptor

- Works with Endurapro's pointing stick
- Supports ISO Layout

and

VendorID: 0e8f (GreenAsia Inc.)
ProductID: 0020
USB-to-PS2 (UP-02)

- Seems to works fine with HHKB and Model Ms on Windows PC
- Sometimes acts extremely weird on Mac OSX when using it with the HHKB, keeps sending the "A" key after each reboot until you replug it?!
- ISO support untested, will add that info later
- Both of above adapters report this ID (they use the same chip?)

VendorID: 10d5 (Uni Class Technology Co., Ltd)
ProductID: 0004
Lindy USB - PS/2 Adapter

- Supports ISO Layout
- Does not support second keyboard in mouse port
- Slow update of status LEDs

VendorID: 04b4 Cypress Semiconductor Corp.
ProductID: 00ff
Cypress PS2toUSB KBM Bridge V2.02a

- no problems known
- works with Model M as far as I remember

VendorID: 0a81 (Chesen Electronics Corp.)
ProductID: 0205 (PS/2 Keyboard+Mouse Adapter)
Hama Konverter USB - PS/2
Belkin USB-to-PS/2 Adapter, F5U119

- Supports ISO Layout
- Mouse port also supports keyboards
- Works well with a Model M13 13H6705

More adapters with this ID:

- This combined USB+PS/2 card includes this Chesen chip.

PS2 to USB Converter (Conceptronic)

PS2 to USB Converter (Huibao)

- same vendor and product ID as Hama, Belkin and Conceptronic devices above
- works with a 1989 Italian (ISO) Model M on OS X Leopard
- support two keyboards at same time
- unfortunately it has the same "device name" as the Conceptronic adapter and so I can't specify different options for different keyboards in Mac OS X system preferences

PS2 to USB Converter (sold under various brands: Sabrent, Cablestar, Cables Unlimited, plus others. Also known as the Bytecc BT-2000. Several websites sell it without specifying a brand name at all.)
Yet another adapter based on the same Chesen Electronics chip.
The picture doesn't show it clearly, but the electronics are molded into the translucent gray USB connector end, and the cables have a metallic look, due to clear plastic over the foil ground shield.
Reported to have "PS/2 reset" issues (keyboard won't accept keypresses for a few seconds, LEDs flash).

Ez Smart Adapter Ez-PU21
VendorID: 0518
ProductID: 0001
- Works with ISO keyboards.
- Alt-PrintScreen doesn't work (have to do normal PrintScreen.)
- Reportedly didn't work with Focus 2001 (link)

VendorID: 0557
ProductID: 0204
Aten UC-100KMA

Works with ISO keyboards
No known issues