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From the August, 1998 PC Alamode:
Computer Monitors:
Fact and Fiction 
by Lee Morris, Alamo PC

Here is a compilation of commonly asked questions about monitors. With proper care a monitor can last longer than your computer. Actually monitors last longer than most computers. This listing is more or less in the order of importance to users. The answers are intentionally non-technical. 

 What is dot pitch?

Dot pitch is basically the size of the individual dots on the display surface. The smaller the dot pitch the tighter, or sharper the image. Today's monitors have .39, .28 or .26 dot pitch with .26 being the highest quality picture (for shadow mask tubes). Trinitron tubes can obtain .25 "apparent dot pitch". The dot pitch is fixed when the picture tube is manufactured and can not be adjusted. What is resolution? Resolution is the size of the work area (or desktop) displayed. Standard resolution is 640x480 lines. The higher the resolution the more information displayed. Read resolution as 640 lines wide by 480 lines tall. Resolution is adjusted with your video card software or "driver". For example: If you cannot see all of a spreadsheet without scrolling left-right or up-down you may increase resolution to 800x600 or 1024x768 to enlarge your view of the document. Increased resolution becomes harder to read on small monitors. 800x600 looks good on 15" monitors and 1024x768 looks best on a 17". What is the difference between VGA and Super VGA monitors?  VGA is basic 640x480 resolution with unlimited colors. Super VGA (SVGA) will display at least 800x600 and 640x480 with unlimited colors. Most modern SVGA monitors will display 1024x768, 800x600 and 640x480 resolutions with unlimited colors. SVGA monitors automatically switch to the resolution set by the video card. My program requires 256 color "Super VGA mode" to operate. Do I need to buy a new monitor?  As mentioned above, all VGA and SVGA monitors display unlimited colors. Your problem is with your video card or video card driver. It takes a minimum of 512k of RAM on the video card to display 256 colors. Most video cards today have 1 meg or more of video ram, which allows 24 bit "True color" operation at 640x480 resolution. The more video memory you have the more colors you may display at a given resolution. The video driver setup software that came with your video card must be properly installed in order to obtain all the combinations of color depth and resolution available. Remember that even a lowly VGA monitor will still do unlimited colors at 640x480 resolution. What the heck is "Refresh Rate"?  Monitors display images by "painting" the image on the screen. The screen is actually painted top to bottom many times per second. In effect the screen is turned on and off very fast. The average human eye cannot see the refreshing of the image just as we cannot see the blinking of most florescent lights. The faster the refresh rate the less likely any blinking will be seen by the user. Refresh rate can be adjusted with your video driver software to match the optimal refresh rate of your monitor. Not all monitors are capable of high refresh rates. 

Adjusting your refresh rate above the monitors' specifications may produce a picture but may also overheat the drive electronics of the monitor, thus shortening its' life. A "vertical refresh rate" of 60hz (60 HERTZ) is standard and a good place to start on most modern monitors. Not all driver software allows manual adjustment of the refresh rate. In Windows 95 selecting the correct monitor type also presets the refresh rates for all available resolutions. Most users will not need to change the refresh rate manually. Tinkering with this setting can be dangerous. One problem worth mentioning though...today's "plug & play" monitors will reset your Windows 95 display settings. If you plug in an older, non-plug & play monitor, after the newer plug and play type, you may be running the older monitor incorrectly. 

 My picture is too narrow or too dim or both.  Your refresh rate may be set too high! Restart Windows 95 in safe mode. If the picture looks fine you may have a refresh problem or a resolution problem or both. Windows 95 safe mode is 640x480 at 60hz (your starting point). Some monitors (especially older ones) do not expand the width all the way out to the edges. This is adjusted inside the monitor and is designed to give a little room on the edges for resolution changes. As a general rule though--if the monitor has a width control on the front it should go "edge to edge" on its' width.  I have an older monitor with a 9 pin plug. Will this monitor work on my VGA video card?  You have a EGA or CGA type monitor. These monitors are completely incompatible with VGA signals. There is no converter plug. VGA & SVGA monitors use 15 pin plugs to the video cards (not all pins used). If you have a female 9 pin plug on the back of the monitor (not on the end of a built in video cable), you may use a PS-2 type 9 to 15 pin video cable to connect to VGA. Samsung and other monitors use this removable cable system on VGA/SVGA monitors. How do I know if my monitor is VGA or SVGA?  Generally, if you have a width control on the front or back of the monitor you have a SVGA monitor. This is not an axiom, but works most of the time. Most monitors manufactured 1992 and above are SVGA with a few exceptions. There is DOS level shareware available that detects video card modes and allows testing resolutions of monitors. We have the software if you need it. How do I measure the size of my monitor? Does size matter?  Monitor sizes are extremely subjective. A 14" monitor class can have a diagonally measured viewable area of 12.5 inches to 13.5 inches. A 15" monitor may be from 13.25 inches to 14.5". The picture tubes are all the same size but the plastic "bezel" (front casing) may expose more or less of the glass. Manufactures measure the entire internal surface of the front glass. When purchasing monitors the "viewable" area is most important. Older Apple & IBM monitors rated monitors by the viewable area not the tube size.  My monitor has a removable video cable with a large 15 pin plug at one end and a small 15 pin plug at the other (both male). The back of the monitor also has the same 2 plugs (female). What is this for?  You have a combination IBM/Apple monitor. Reverse the cable to match the computer you have. I have been told to leave my monitor on all the time. Is this a good idea?  Not really. Monitors are basically light bulbs. Tubes degrade with use and electronic components wear out. If you leave your computer on you should turn off your monitor. The new "energy saver" monitors will turn off for you if you setup the power management features in your BIOS or operating system. All I did was bring my monitor from one house to another. Now it seems to be broken!  When you bought your monitor it came in a box. The swivel base was removed and the monitor was suspended in Styrofoam. When you moved it you set the monitor in your trunk sitting on the swivel base. A few pot holes later the monitor bounced and cracked the printed circuit boards located directly above the swivel base. If you no longer have the shipping box, place the monitor face down on your car seat with a seat belt wrapped around it. In the trunk place it face down or on its' side with a blanket underneath. All I did was move the monitor from one computer to another (in the same building) and now the colors are distorted. What gives?  Monitors are magnetic devices operating in the Earth's magnetic field. The metal components of your monitor become magnetized by the Earth and other sources of magnetic fields. A strong electomagnet is built in the front case of all monitors. This electromagnet is oscillated (briefly) each time the monitor is turned on. The electromagnet "degausses" the monitor's metal parts, thus reducing color distortions. The monitor was warm when you unplugged it and warm when you plugged it in again. It is not facing the same direction as it was in relation to the Earth's magnetic field (North-South for example). Don't panic! Don't move the furniture! All monitors have a degaussing circuit. Some have manual degauss buttons on the front or back. There is a device inside that degausses the monitor automatically one time, every time it is turned on cold. The monitor must cool down first then be turned on again. Sometimes it takes several cycles to degauss the screen. I have two computers side by side. Both monitors are wavy, why?  The magnetic fields of the two monitors are interfering with each other. Keep them at least 3 feet apart. This distortion can be caused by other magnetic devices also. Speakers, clock radios and telephones are a few examples. My colors look very strange! How do I know if it's my monitor or my video card causing the problem?  Most computers today have a Windows game called "Solitaire". Start up Solitaire and look at the cards. The cards should be pure white with red diamonds & hearts. The background around the cards should be pure green and blue is found on the backs of the decks. These are your 3 primary colors. If any of the 3 colors are missing your monitor is probably defective. Other problems like "ghosting," over bright or too dim are also monitor problems. Video card problems usually involve sharply defined blocks or lines of incorrect data with all 3 colors displayed.  My monitor has two very thin lines running left to right. What are they?  You have a "Trinitron" type picture tube. Most monitors are "shadow mask" types that have a fine dot screen behind the front glass. Trinitron picture tubes have tiny wires running up and down the screen. The 2 thin lines hold the wires straight. This is normal. I bought this old 19" monitor real cheap! It has three BNC type connectors on the back, no cable. Where do I get a cable to hook this up to my PC clone?  Welcome to "fixed frequency" monitors! Your monitor may be old Apple/Mac or some custom application odd ball system of old. Some had 3 BNC's some 4 and some 5 BNC connectors. Most will display only a single fixed resolution and refresh rate. These monsters can be hooked to PC's with special video cards that cost upwards of $300 each. The best source for cards & special cables is Griffin Technologies. Search the web, you can't miss them. Lots of luck! I just bought a new plug & play monitor for my old 486 system. My old monitor works fine but the new one has no color in DOS, only black & white. Is the new monitor bad?  Your old video card is miss reading the new plug & play monitor as a MONO VGA. Pin 11 of the old video plug standard no longer is used for mono VGA. Try putting the command "mode=co80" in your autoexec.bat file. It this does not work you will need a newer video card.  How do I clean the outside cabinet of my monitor?  We use a strong cleaner, such as "Fantastic." You must take care not to spray into the vent holes on the top or sides of the monitor. Do NOT use steel wool! Steel wool's small steel wires can get into the unit through the vent holes and cause a short. If your monitor has turned yellow there is not much you can do. The yellow is caused by direct exposure to sunlight or the natural transition of some cheapo plastics, or both.  How many magazines can I stack on top of my monitor? The vent holes on top of your monitor must not be blocked! The vent holes on the back and bottom must also be clear from obstructions. Installing your monitor into a cubical, as in a role top desk or cabinet, is not a good idea. Air flow is CRITICAL to the extended life of your monitor. If you remove the swivel base on your monitor be sure there is still room for airflow through the bottom vents. Just because a swivel base can be removed does not mean it should be!  I have a pocket screwdriver! So how do I make my own internal adjustments to my monitor?  Monitors have very dangerous voltages inside the cabinet. Not only can you give yourself the shock of your life, you can also create an unsafe radiation environment. If you find the control to disable the HIGH VOLTAGE PROTECTION circuit and then turn up the ANODE voltage for a brighter image, you can bring the HIGH VOLTAGE above 33,000 volts and effectively X-RAY yourself. So if you wish to alter your gene pool give it a try! We strongly suggest you DO NOT open the cabinet at all. What is the best monitor to buy?  The quality of monitors changes from model to model and year to year. Generally you get what you pay for. The most important factor, beyond, how it looks, in our opinion is warranty. Retail stores usually have better prices than local dealers but have short warranties, usually 12 months. Local dealers sell "OEM" monitors (Original Equipment Manufacturer) that carry a 3 year warranty with the first 12 months being an over the counter swap. Ask how the warranty is provided. Ask if you must pay shipping both ways. Some companies provide advance replacements. Remember, a 17" or 19" monitor can be rather expensive to ship! If you pay with a "gold" credit card you can sometimes extend the warranty.  Lee Morris, owner of a monitor repair shop in San Antonio called Morris Technical Services. Lee has 24 years experience in electronic repair in computers, video games & others. Morris Technical repairs monitors, power supplies, terminals & other computer related electronic components. Phone:(210)530-0986 e-mail "mortech@juno.com"