IMac Display as Monitor for PC

Question

I have an iMac 2.66 GHz Intel Core 2 Duo, 2 GB RAM, OS X 10.6.2 and an old Dell Pentium III 933 MHz which I would love to somehow connect together. I am considering to install Linux on my Dell and use both computers for different reasons. I wonder if I would be able to use my iMac like a monitor for the old PC.
I have come across the following discussions but it seems that they don't cover my case, i.e., an old Dell that does not have a port for a display port.
http://discussions.apple.com/thread.jspa?threadID=2246912
Any suggestions and thoughts would be most appreciated.

Answer 1

Ron-
There are more details here--
http://discussions.apple.com/thread.jspa?threadID=2205633&start=30&tstart=90
--but the basic problem is that you need a DisplayPort signal to drive the iMac monitor. You can convert a digital DVI output (or HDMI which is the same thing with audio and a different physical connector) to DP format with an expensive converter, but there is no way to convert an analog VGA signal to DP format. The cheaper but more complicated solution for a PC with DVI output, and the only solution for one with VGA output, is to replace your video card with a DisplayPort or Mini-DisplayPort card. Mini-DisplayPort has the same signal but a smaller physical connector.
This was not actually Apple being arbitrary: DisplayPort is more efficient and less expensive than DVI/HDMI because it dispenses with a lot of the conversion hardware needed for that format. Therefore Apple couldn't provide DVI/HDMI compatibility without increasing the iMac cost substantially.
-JAFDC