General discussion


PC will only run in safe mode

By alane ·
I have a PC which will only run in safe mode.
Some time ago this particular PC started to randomly reboot so I took it out of service until I could get some time to investigate the problem. The PC was relatively inexpensive and I am only trying to find out why this is happening for my own peace of mind as it is now driving me completely round the bend.
The symptoms are -
1. either enters a reboot loop at POST (may do this 5/6 times then goes to 2)
2. loads OS OK but will 'switch off' as though the plug has been pulled at random intervals
3. As 2 but switch off at first keystroke or mouse movement.
4. Occasionally will allow 2/3 minutes use then as 3
After 2,3 or 4 will run scandisk then as above
In attempt to fix, I initially reinstalled Win 98 SE from scratch after reformat.
Since then I have -
fitted new hard drive
new memory
installed (at different times) both Win98 & Win2000 OS
Booted computer with every combination of System configuration.
The PC spec is -
BK630e V1.7D / V7.1 MAINBOARD
CentaurHauls x86 Family 6 Model 6 Stepping 2
240mb ram
OS Win 98SE

I have discounted faulty PSU as the problem as the PC will run indefinitely in Safe Mode
Any assistance will be greatly appreciated

This conversation is currently closed to new comments.

Thread display: Collapse - | Expand +

All Comments

Collapse -

by w2ktechman In reply to PC will only run in safe ...

sounds like a virus, I would reinstall after fdisk /mbr

Collapse -

by alane In reply to

Definitely not a virus - clean install on new hard drive after fdisk did not fix problem, Thanks anyway

Collapse -

by NeedsAVacation In reply to PC will only run in safe ...

Might be a bad power supply too. If it's relatively inexpensive, I wouldn't beat your head against the wall too much. It's no fun doing that.

Collapse -

by alane In reply to

Thanks - this confirms exactly what I know I should do - trash the PC. I just hate to be beat.

Collapse -

by RCOM In reply to PC will only run in safe ...

Because the PC runs in safe mode doesn't mean there isn't a power problem. In safe mode a device may not come on that otherwise would overload the power supply.

First if any, what changes have been made to the hardware or software. Is there anything different with the surroundings like another device plugged in to the same surge protector or power outlet. In otherwords start outside and work your way in. This may just be a loose power connection. After illiminating outside sources then dig into the PC.

What happens if you boot to a command prompt with a boot disk. OS doesn't matter cause you're just seeing if the PC will stay on. If it does then its a software related issue.

In safe mode uninstall drivers for modem, sound, nic, and all external peripherals connected USB, COM and LPT ports. After shutting down physically disconnect them. Only connect a regular keyboard & mouse. In the BIOS, disable hardware monitoring, the onboard devices like modem, a common cause of this problem, network card, sound, COMM and LPT ports. Sometimes there's jumpers on the mother board to disable the onboard devices if so look in the users manual for how to do it. If you have a video card disable the onboard and install that.

Start the system if it works add items one at a time until the problem occurs. If its an onboard device you can leave it disabled and use an add-on card.

Collapse -

by alane In reply to

Poster rated this answer.

Collapse -

by cglrcng In reply to PC will only run in safe ...

If it will run indef. in Safe Mode, then I would suspect either an add in card like Video, modem, etc. or a specific program in your start up folder. Try this first in Win98SE. Start it in Safe Mode, then Start>Run>Type: msconfig>Enter

1st thing to do is click on the button "Create Backup", and follow the instructions to create a backup even if a recent 1 has been made.

(Now get out a pen & paper and make a simple chart of the 6 checkboxes below the "Selective Startup" section) You will be trying many combinations so keep track of that which you have checked out already.

Check the circle for "Selective Startup", uncheck "Load startup group items". Restart the computer. If it loads Windows normally, then it's simply a program in the start-up folder. Here's what you absolutely need to run Win98SE only, not counting your AV and other optional start-up items. If it starts normally, then go back to msconfig, re-check the "Load startup group items" box but leave it in the "Selective Startup Mode", go to the "Startup" tab up top, then uncheck all items except the following.

Scan Registry
Task Monitor
System Tray
Load Power Profile (there needs to be 2 separate entries of LPP, DO NOT uncheck either of the "Load Power Profile" items).
Scheduling Agent
Load QM- If Present (if you uncheck it, then it will just create another entry upon re-boot, not good).

Ucheck all others present. Re-start the computer and see if it starts normally (if it does then the only items in the system tray by the clock should be the Task Scheduler & Volume Icon).

Now you have determined that it is a startup item or hardware associated w/1 of those items. I would go back to the start up tab, keeping track of what I do, and recheck the boxes for those other startup items 1 at a time and restarting normally until I had a shutdown, freeze or whatever the original problem was until I found the program that causes the problem.

Collapse -

by cglrcng In reply to

If it isn't located in the startup folder...Then return to the msconfig "Selective Startup" area again, working from the bottom up uncheck the next item also & uncheck "Process Win.ini file", and so on till the problem goes away and Windows starts normally. Once you find out where the problem is located we can better help you. Keep good records!

Good luck on your search. I'd also think about finding a test PCI video card and removing and replacing the existing card (change the driver of the installed card to a standard vga driver before removing it & restart, then remove the physical card), and remove all video driver entries present (NVidia, Real3D, etc.), using Add/Remove Programs. Remove the modem & NIC & any other add-in cards. All you really want is the CPU, Keyboard, Mouse, a simple PCI Video Card, & the Monitor. No printer, Scanner, Camera, etc. attached to the puter. I'd go as far as removing (unplugging) any drives (including power connectors & ribbon cables), except the hard drive (you might laugh but have seen a malfunctioning CD or Floppy drive hang Windows up bad).

Collapse -

by cglrcng In reply to

Re-read your post, if you have tried all the above...Download & install WinSafe from; install it and start the puter in Safe Mode, then print out the BootLog.txt file located in the folder or on the winsafe control panel. Had to do this once and go line for line through the boot process looking for load failures (the log was like 87 pages long, be warned). My problem was a failure do to a bad uninstall of Zone Alarm leaving files behind. Always shut it off before uninstalling.

Good Luck, but do list your start up files on the startup tab, K? I'll go over the list if you do.

Collapse -

by Joseph Moore In reply to PC will only run in safe ...

Bad motherboard?
Did you try upgrading the BIOS on the motherboard? If so, then get a new motherboard.

Related Discussions

Related Forums