My computer locked up, and the red activity light was on. The three finger salute had no effect and the off/on button was of now use. I had to unplug the cpu to have it reboot. What gives guys? Thanks, Pete
This question was answered on August 22, 1999. Much of the information contained herein may have changed since posting.
Explanation: The system is booting up and starting to work correctly, but on occasion it either reboots without warning, or seizes hard (no mouse or keyboard response, and a reboot is necessary) These symptoms occur over a period of time.
Diagnosis: This is, unfortunately, one of the most difficult of all problems to troubleshoot on the PC The reason is twofold: first, these problems are usually intermittent, and therefore hard to pin down to any particular cause, and second, there is a really large variety of problems that can cause this sort of behavior It is necessary to narrow done the specific circumstances in order to have a better chance at finding the problem See below for possible causes, which are listed with the recommendations to possibly solve them.
Recommendation: Follow the questions and suggestions below to try to identify the cause of the problem:
Did you remember to scan the system for viruses? Lockups and instability are "classic" virus infection behavior
Make sure that you disable all power management options in the BIOS setup program They can cause spurious behavior, particularly on some motherboards
Are you getting error messages when the problem occurs? Are you experiencing this problem only when running a specific application program? If so, it may be the application itself that is causing the problem
If the problem occurs only when you use a specific peripheral, such as a mouse or modem, there are three typical possible causes specific to this situation First, there may be a problem with the particular peripheral you are trying to use Second, you may have a resource conflict that is causing the system to lock up when you try to have two devices access the same resources Finally, there may be a driver problem with the device, if it is something that uses a driver in the operating system you are using
If the problem occurs only when the system is warmed up (meaning not within the first few minutes that the PC is turned on, but only afterwards), or if the problem occurs only when the room where the PC is located is hot, it is likely that the problem is hardware-related and probably something to do with the motherboard, processor or another system component that is running too hot
Are you running a VESA local bus video card on a motherboard that supports both VESA and PCI? If so, you should realize that this combination has been known in the past to cause instability Try replacing the VESA video card with an inexpensive PCI video card and see if the problem goes away
If the problem is occurring under Windows 3.x or Windows 95, try using just DOS software for a while and see if the problem goes away If it does, then you may have a problem with your installation of Windows, although it could still be a hardware problem (Windows is more sensitive to these than DOS is)
If you have a network card, check your network settings Sometimes the built-in networking in Windows will spend a great deal of time "looking" for a network when one is not there, which causes the system to lock up and then unlock periodically If you are using TCP/IP or another protocol, try disabling the protocol and see if that fixes the problem You may need to contact your network card manufacturer or Microsoft for more assistance if this is the case
If you have recently changed any BIOS settings--especially those that control system timing--and the problem has started since around that time, try changing the BIOS setting back to the previous value, or resetting the BIOS settings to low-risk defaults to see if the problem goes away You may also want to follow this procedure to set your key BIOS settings to safe values
Scan the hard disk for file system corruption and check for bad sectors as well
Drivers can cause seemingly random glitches and lockups if they are poorly written, especially the video driver Try running the system with a "slow but sure" default driver or a different version obtained from the manufacturer Sound card drivers can also be touchy in this way Try turning off hardware acceleration in Windows 95 by selecting System in the Control Panel, then selecting the Performance tab and clicking "Graphics"
Unreliable power can cause all sorts of strange system problems A common problem is having the input voltage selection on the back of the power supply set to 220V when it should be 110V If possible, try running the system off a UPS and see if the problem goes away If practical, try swapping in a new power supply If you notice the lights dim briefly at around the time that this problem occurs, this is a power problem
Try using less aggressive BIOS settings for items such as memory timing and hard disk timing For example, set the BIOS memory access settings to the slowest possible Disable any performance-enhancing BIOS options (such as those described here) to see if the instability goes away Try running the hard disks at a lower PIO mode to see if IDE timing might be causing the problem
Under Windows 95, make sure you have a sufficiently large swap file enabled A too-small swap file may cause problems If you have been tinkering with the virtual memory settings this may be the cause of the problem See this section for ideas on swap file size optimization
Check for resource conflicts
Troubleshoot the processor
Troubleshoot the system memory Memory problems are a frequent cause of crashes and other spurious behavior
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Posted by Ken Colburn of Data Doctors on August 22, 1999