The monitor works fine on another PC, but my Dell Dimension desktop PC won’t display video/graphics

PROBLEM: My ageing Dell Dimension C521, upgraded to Windows 7 Home Premium, won’t display video all of a sudden. The monitor works fine with another PC, the keyboard lights up, the hard drive can be heard whirring and the DVD writer appears to be working properly, so I am led to the conclusion that the low-profile ATI X1600 graphics card with analog VGA and S-video ports is probably responsible. I need to access my files urgently. Is it possible to use the S-video port to output a video signal to a TV? Or can I install the hard drive in another desktop PC?

ANSWER: If you have a spare PCI or PCI Express video/graphics card, try removing the existing card and installing it. If it works, then the graphics card is responsible. All of the fans, particularly the fan cooling the graphics card, if it uses one, which your ATI X1600 card does, and the processor, which all use one, must be working. If the fan used by the processor’s cooling unit has failed, the PC will shut down and fail to boot automatically before it can boot to protect the processor from destruction by overheating, so it has to be replaced.

Here are a few other troubleshooting tests to perform:

1. – Press the Num Lock and Caps Lock keys on and off. Do the corresponding lights on the keyboard come on and go off? If not, the computer is not booting properly, having crashed at some point.

2. – Is the hard-drive LED light indicating disk-access activity by going on and off rapidly and continuously. If the answers to both 1. and 2. are affirmative, Windows might be booting all the way if no password is required, but due to a faulty or loose or badly-cabled video card can’t be seen doing so. If a password is required it could be booting to the login screen.

3. – If the answers to 1. and 2. are negative, the computer is not booting. The first action to take is to open the side of the case that gives access to the components, usually by removing the screws at the back of the case. Remove all of the removable adapter cards (graphics card, sound card, wireless adapter, etc.) and memory modules, clean their connectors lightly with a rubber (eraser) use a hairdryer on blow to blow any dust out of the slots and reseat them. You can use your breath to blow dust out, but should use a hair dryer to get rid of any moisture that might have been introduced. Doing that to the video/graphics card can fix a poor connection. Make sure that all of the cables are connected properly and are not damaged. The processor is rarely the cause of this kind of problem, but, just in case, remove its cooling unit and remove it from its socket by lifting the lever beside the socket that releases it, remove any dust from the cooling unit and the socket, reseat it, making sure that it is correctly aligned (if necessary read the Build Your Own PC section of this site under the Hardware menu for information about processor/socket alignment), push the lever down and make sure that you replace the cooling unit properly. It must be firmly attached to the processor without any gap between it and the processor.

4. – Note that when switching a PC off, you should power the PC down and switch the mains off. If the problem remains, switch the PC off at the mains, remove the RAM memory module(s) and switch the mains on and turn the computer on. If you hear a beeping sound, which is a beep code sent by the motherboard’s BIOS setup program, then the memory is responsible. The PC’s user manual or the user manual provided by its motherboard’s manufacturer usually provides the information about what each beep code means, but you don’t need to know that information in this case, you just have to know that a beep code is produced when removing a particular component. If there is more than a single module, switch everything off as before, install each module in the first DIMM memory slot, which should be numbered, and switch the PC on. If the memory passes the test by not beeping, switch the PC off and try removing the video card, which is probably the bad component if a beeping sound is produced. Buying a new PCI Express video card is not a problem because your PC has the required long x16 slot. The Sapphire Radeon HD 5450 is a good, inexpensive choice. If not available new, eBay is a good source of good secondhand components. I have just had a look for your graphics card there and saw many available priced at £20.

5. – If the problem still exists, try removing the processor from its socket, having first removed its cooling unit. If a beeping noise is produced, the processor is probably the cause. If not, the motherboard itself is probably responsible. Since it connects all of the other components, it can’t be removed without installing a replacement board. You will have to buy a replacement of the same make and model in order not to have to reactivate Windows 7 (read Product Activation on this website under the Software menu for more information on it), because changing the make/model of motherboard is seen by Microsoft as having a new computer. Given the age of your PC, you will only be able to buy a second-hand motherboard of the same make/model from a site such as eBay. If you have a retail copy of Windows, you will still have to reactivate Windows but you can use it as many times on a single computer as you like as long as only one machine is running it at a time. But if you have an OEM copy of the kind provided by Dell, you have to reactivate Windows, which probably won’t reactivate due to the way that activation treats a new motherboard, so you’ll have to phone Microsoft and speak to a support person, who might give you a reactivation code or might ask you to buy a new licence.

An S-video port can’t be used to access your files because it cannot be used to interact with Windows only to output video to a TV.

If you can’t get your PC working by using the troubleshooting information provide here, given the age of the PC, the best option would be to buy a new one, remove the old PC’s hard drive and then install it in the new one in order to be able to transfer its data files across to the new PC’s hard drive. Your new PC will support SATA hard drives, but not necessarily the older IDE PATA hard drives, which usually use wide ribbon cables. If your old PC has an IDE PATA hard drive and your new PC doesn’t have an IDE port on its motherboard, you can install the IDE drive in an external IDE-supporting USB caddy, costing about £10, which connects to the PC via a USB port. The old drive will then show up as a drive with a letter higher than the C: boot drive under Start => Computer in Win7 and you can then copy your data files across to the corresponding folders in Windows 7 by using Windows Explorer.

All of your software applications, tools, scanners, web browsers, etc., will have to be reinstalled on the new PC.

About Eric 275 Articles
I am an experienced PC technician who has been the owner and sole writer of the PC Buyer Beware! website since 2004. I am learning all the time in this very dynamic, ever-changing field.