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Scouse Monkey · 04-19-2005, 03:21 PM

POWERING YOUR SCREEN OFF YOUR PC POWER SUPPLY:

Although certain screens may be quoted as being able to run off 12-24V it can be seen that there is a risk of prematurely killing your CCFL (if not the rest of the components) as the CCFL quite often goes brighter when the screen is connected direct to a car battery (>14V) compared to a 12V supply. This shows there is no or poor regualtion of the input voltage which may cause damage. It shouldn't do as the manufacturers should be underating the inverterif this is the case but regardless your car is not a clean 14V supply and has a lot of spikes and noise - especially during cranking.

It has been widely accepted that the best way to preserve your LCDs health and also a quick and easy way to make sure it turns off and doesnt drain your battery (even in standby it will drain your battery - all be it slowly) is to power it off the 12V line onf your PCs PSU.

On a molex conenctor this is the Yellow wire (12V +ve) and you also want to use the adjacent black wire for -ve.

If you power your monitor in this way you do not have to use the 12V regualtor that comes with it - doing so as well may introduce noise and also cause your screen to be dimmer due to a voltage drop. It is also one more thing to go wrong.

The power of most 250-400nit 7" LCD monitors, and indeed 8" models, is about 10W which is about 1A on your 12V line so make sure you have enough power for it.

If you don't you can use a cheap and simple 1-1.5A 12V DC-DC regulator such as those that come with some screens or ones you find to power portable DVD players. 1200mA models are quite common. These can normally be connected to your ACC line (switched 12V line your HU) as the power is low or you can connect them direct to the battery via a relay that is powered by your PCs PSU or the ACC line. The ACC line or relay and ACC line may be prefered so your screen does not stay on after you have left the car and the Pc is shutting down.

Some of the DC-DC regualtors that come with the screens may be okay to use - you don't have to go out and buy a new one but if possible check the voltages coming from your supply while the engine is running and also check for the screen going brighter when the engine is revved.

04-19-2005, 03:21 PM	#4
Scouse Monkey MySQL Error Join Date: Mar 2004 Location: Bristol Vehicle: Pug 306 & BMW 325i Posts: 13,521 My Photos: ()	POWERING YOUR SCREEN OFF YOUR PC POWER SUPPLY: Although certain screens may be quoted as being able to run off 12-24V it can be seen that there is a risk of prematurely killing your CCFL (if not the rest of the components) as the CCFL quite often goes brighter when the screen is connected direct to a car battery (>14V) compared to a 12V supply. This shows there is no or poor regualtion of the input voltage which may cause damage. It shouldn't do as the manufacturers should be underating the inverterif this is the case but regardless your car is not a clean 14V supply and has a lot of spikes and noise - especially during cranking. It has been widely accepted that the best way to preserve your LCDs health and also a quick and easy way to make sure it turns off and doesnt drain your battery (even in standby it will drain your battery - all be it slowly) is to power it off the 12V line onf your PCs PSU. On a molex conenctor this is the Yellow wire (12V +ve) and you also want to use the adjacent black wire for -ve. If you power your monitor in this way you do not have to use the 12V regualtor that comes with it - doing so as well may introduce noise and also cause your screen to be dimmer due to a voltage drop. It is also one more thing to go wrong. The power of most 250-400nit 7" LCD monitors, and indeed 8" models, is about 10W which is about 1A on your 12V line so make sure you have enough power for it. If you don't you can use a cheap and simple 1-1.5A 12V DC-DC regulator such as those that come with some screens or ones you find to power portable DVD players. 1200mA models are quite common. These can normally be connected to your ACC line (switched 12V line your HU) as the power is low or you can connect them direct to the battery via a relay that is powered by your PCs PSU or the ACC line. The ACC line or relay and ACC line may be prefered so your screen does not stay on after you have left the car and the Pc is shutting down. Some of the DC-DC regualtors that come with the screens may be okay to use - you don't have to go out and buy a new one but if possible check the voltages coming from your supply while the engine is running and also check for the screen going brighter when the engine is revved. __________________ If you want more answers on anything I have posted you can find me at digital-car.co.uk or skiing or diving or doing somthing else fun! Last edited by Scouse Monkey : 04-19-2005 at 07:32 PM.