The first thing you need is a 5" PSOne screen, it's better to use the official SONY PSOne screen as this guide will cover instructions for this particular one, also, other brands may not have the required TV-in connectors. You can get a PSOne screen for less than £30 including postage, brand new from eBay. You may be lucky to find them in the high street or any other online retailer, it is unlikley due to the fact the PSOne is now 6 years old. The official Sony PSOne screen looks like this:

Flatten out the screen (as below) and with a flathead screwdriver, try and get the speaker meshs off, then take off the foam (it may be a little sticky). There are more screws in here, unscrew them. When done take off the screw caps at the top of the screen, and unscrew the screws in them. Finally unscrew the 3 screws at the bottom of the screen. All shown in red below:

You should now be able to take the back cover off with ease. Do so, and be very careful to not to pull any cables, especially the ribbon cable in between the screen and PCB (Printed Circuit Board - the green board behind the screen itself) , keep the front cover for now. I suggest you tape the screen to the PCB board (keep the screen's protective covering on to avoid scratches).

Once the covers are off, at the back there are two large screws at the bottom, unscrew them to get access to the small PCB board, very carefully disconnect the three wires attached, they should be relatively simple to pull off. Don't worry about getting the cables the wrong way round when you put them back, each wire will only fit back in it's own slot.

Then unsrew the last 6 screws at the centre bottom. The only plastic you should now have is the front cover. After reconnecting the wires (they only go in their own slot, and only in one way) you should be left with:

Cut off the wires connected to the speakers and remove the front plastic. If you are using PAL (That is Europe, Australia and New Zealand) you will need to do a simple modification to power the backlight of the LCD, to do this, cut the leftmost wire of the right connector (the one with some blue wires on it) and solder this onto the circled area below. Make sure the wire has been cut at the small PCB end, not the main PCB:

You now need some cables to connect the screen to the computer, to do this using S-video you need:

Composite to 3.5mm jack, which is also known as a camcorder lead, which often comes with digital camcorders, you MUST have the yellow video phonos at the end, not just red and white. £4.99 at Maplins:

RCA to S-Video adaptor. £4.99 at Maplins:

S-video cable, this will come with most digital camcorders, and with graphics cards that have S-video outputs. £4.99 at Maplins:

Notes

• You can most likely buy these wires at places cheaper than Maplins, such as eBay, online cable shops or in other audio/video retailers, these here are just a guide to what you need.
• If your graphics card does not have S-video output (if you are unsure, look at the back of the graphics card and see if you have a round black port, if you do then you can use S-Video. If not you can either by a new graphics card with S-Video/VIVO/HDTV outputs or use an alternative (much harder and time consuming) method of connecting the screen here, however this is not reccomended if you have an nVidia graphics card.
• Instead of an RCA to S-Video adaptor, you can get an S-Video to Composite adaptor with 4 pin female headers at the S-Video end. If you get this an S-Video cable is not required, they look like this:
  
• If your graphics card's S-Video also supports VIVO/HDTV the S-Video connector on the graphics card will be 9 pin (if you look closely there will either be 4 or 9 round holes) then you will need a VIVO adaptor, this will come with your graphics card.

Mount your screen to wherever you want. It fits perfectly into 3 floppy drive bays, however the PCB board takes up more space, just a little taller than 3 cd bays. Connect the cables in the following order:

PSOne screen TV-in port (the black port above the green audio port on the small PCB) --> 3.5mm jack to yellow composite --> RCA to S-Video adaptor --> S-Video cable --> VIVO adaptor (if necessary) --> Graphics card S-Video Out

Plug in the power adaptor to the screen into the mains and turn it on, then turn on the computer, you are now done.

It may be necessary to configure your OS to display something on the screen, in Windows right click the desktop and go to Properties, under the Settings tab click on the second screen and select Extend my Windows desktop onto this monitor. Set the resolution to 640 by 480 pixels.

Because the PSOne screen uses 7.5v of power, you need to convert the computer's 12v to 7.5v, as a car's battery supply is also 12v, you can modify a PSOne car adaptor for the computer. Pretty much the only place you can buy the PSOne car adaptor is from eBay

Cut the cigarette lighter end off (the cable is quite long, so you may wish to cut it shorter, leaving some slack) and splice the cables, the black cable is positive, the black cable with the white line is ground.

Cut off a male end of a Molex cable and discard it. solder the positive on the car adaptor to the yellow 12v line on the female molex connector (It MUST be the yellow wire) and solder the ground to the black wire next to the yellow on the molex connector. Tape each solder joint separatly and you are done.

Connect the molex to your computer's power supply and the other end to the PSOne, your screen should now be powered by the computer.