Apple document details Target Display mode for 27" iMac

I want to use the iMac as "target DISPLAY" I have a display port to VGA converter.
I connect my pc vga out port to the VGA converter. The iMac detect the signal and try
to use the pc as a second display, but I am not able to put the iMac as "target display"
It is possible to get this "Target display"with this display port to VGA converter ?
what about a display port to DVI converter ?
or It is only possible using devices with outpud display port and display port to display port cable ?

so i was wanting to use the iMac as both a display and a windows machine.. (beats a virtual machine) how would the keyboard switching between target display mode from windows work?

I have a friends old dell and a early 2008 iMac 24" how do I make my iMac monitor a monitor alone?

Here in Australia, the 27″ iMac base model retails for $2068. This is only $570 more than the 24″ Apple LED Cinema Display.

Contrast this to the Apple 30″ Cinema HD Display for $2798, and the iMac has a built-in computer. Get the 27″ iMac instead and use it as an Xgrid render node, use it as a NAS, use it as a Time Machine disk, use it as an Xcode distributed compiler or just keep it as a spare computer if the main one goes down.

The only downside I can see to this is the power consumption of having a second computer running as you can’t use the iMac as a display without having it turned on (well, obviously) but that means that the computer behind the LCD is powered up and running. You can idle the CPU and spin down the hard drive to save power, but a standalone display will still use less power.

With the Quad-core i7 iMac beating the Mac Pro in just about all benchmarks at the moment, you can get one base model 27″ iMac as a display and the Quad-core i7 iMac with 8GB of RAM for just over $5k. To contrast, a Mac Pro Quad-core with 8GB and two 30″ displays will set you back more than $10.5k…

I'm not sure if all of you've read all the articles online concerning the use of other devices with the imac as a monitor but it is just not possible even with a little adapter. Apple specifically states it will only work from a device that has a display port out and a little $20 adapter will not solve this for PS3s or other devices since the technology is completely different. It will require a video conversion box that will probably run around $200 which is already available but has not been confirmed to work yet since probably no one has dropped that much money just to use the imac as a monitor for some other device. The display port technology in the imac is not designed to convert DVI video inputs since electronically they are completely different form one another.

Yesterday I was replacing my iPhone and enquired about using the target displayed iMac as a 'headless' server (primarily for fcp and ae rendering). The genius said 'nope', apparently the CPU etc go into a sleep mode and makes functions other than target display inaccessible.

This makes me wonder if the i5s can do it too but Apple is just limiting them

i really want to try this ... (once apple get the finger out and deliver it ... nearly a month ago i ordered my quad core.. :ss)..

I'm tempted to get the low end 27 inch iMac since it's $100 cheeper then the non LED lit 30 inch Apple display. Not sure what I'd do with the computer part though, and it's a shame it has to be fully booted for the target display mode to work. Not very energy friendly if it's used only as a monitor.

I'm just waiting for an adapter that let's me use my Xbox 360 with it.