Cheap USB Monitor with DisplayLink Graphics Chip for thin/zero client computers
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This is a copy of a message I posted in earthtreasury group.
I came across some information on a new Samsung U70 USB monitor with embedded DisplayLink graphics chip, that I thought might interest you. Instead of using a graphics card in the PC, you just have a software display driver. The driver compresses the display data and sends it by USB cable to the monitor. The DisplayLink chip in the monitor then decompresses it, and acts as a graphics card to render the picture.
As you know, the Sugar interface used by the OLPC can also run on other Linux Computers. Many people may want to try Sugar or use it with conventional PCs.
People have put forward various solutions to providing lots of computers at a low cost per 'seat' :-
1) Thin Client computing - A Server PC + one low-spec Thin Client PC per person with monitor, keyboard, mouse and speakers.
2) Zero Client computing with one interface box per person - A Server PC + an interface box per person with graphics card and sound card, connected to a monitor, keyboard, mouse and speakers.
For example, the Hubster by Ndiyo http://www.ndiyo.org/
The Ndiyo site has links to drivers used to set up multiple zero-clients on a server, for monitor and keyboard.
2) Zero Client computing with everything connected to the server by USB - Until recently, USB monitors with embedded graphics card were very expensive. Samsung has now produced a cheap (55 GBP or $90) 7 inch USB-connected monitor, with a DisplayLink chip built it. See the link below to a picture of it being used with a Router as a cheap Linux computer.
Samsung and many other manufacturers are now including chips from DisplayLink Ltd into their monitors, so they are USB-connected and plug-and-play. The advantage for Zero-Client computing is that you don't need 'one graphics card per seat' fitted in the server PC (or dual/triple/quad head graphics card from Matrox etc). Instead, you could have 5 or 6 zero-client computers by connecting a 1-to-4 USB Hub per seat to the server. Each USB Hub then connects to a Samsung U70 7 inch monitor + Keyboard + Mouse. The cost per seat would be about $100. That is like the original target price of the OLPC. Fine for school use, but the kids can't take it home.
The real advantage comes in the power saving. A typical PC uses a 300 Watt PSU and consumes about 80 Watts in normal use. If you had 6 normal PCs, you would need 480 Watts on average. The Samsung U70 only consumes 5 Watts, so you could add those to 1 server PC without using much more power at all. 80W + (6 x 5W) = 110 Watts. That's a lot better than 480W.
In a school, a large part of the cost is provided electric power. There's a high capital cost if you use rooftop solar panels, or a high on-going cost for generators or taking car batteries for recharging. If zero-client computing can reduce the power requirements, it may be quite useful in some situations.
I was thinking this zero-client setup with Samsung U70 monitors might be useful in some situations...
1) In a country that isn't taking part in OLPC, so can't get OLPC Laptops.
2) Where a school already has 1 PC and power supply.
3) Expanding a laptop by adding more 'seats', to 5 or 6 kids could use it. The whole setup could be moved around, from classroom to classroom or school-to-school, etc.
4) It could add a very-low-power monitor to almost any kind of new or old PC or Laptop.
5) The U70 could act as a low-power replacement screen for a laptop with a broken screen (often sold off very cheaply).
For more info on DisplayLink chips, see...
The DisplayLink shop page lists monitors and VGA boxes that use the chip...
If you watch this video on the Ndiyo site, it demonstrates the whole setup, but the video was made about a year ago using a larger Samsung Monitor with embedded DisplayLink chip. It would be the same setup using the cheap 7 inch Samsung U70.
I think all the companies are related, through the design a implementation of the chip; Ndiyo, DisplayLink and another one called CamVine that Ndiyo mention.
Anyway, I thought I'd float a few ideas, to you and the OLPC and Sugar people that you know.