Q: I built my own PC and it is running on Windows XP Professional and Ubuntu 9.04, Jaunty Jackalope.

For the past three months, I have been having problems with the keyboard and mouse. The monitor also freezes from time to time.

When running either Windows or Linux, I notice that the hard drive light is still flashing, indicating that the operating system is still accessing the hard drive. So it may not be a hard disk failure.

I have removed the RAM modules and now my PC cannot start up.

My PC's specifications are as listed:

• Motherboard: MSI P6NGM-FD
• Intel Core2 DUO processor E8400
• Asus 8400GS PCI-E graphics card
• WD 750GB 7200PM with 6MB cache
• Sata HDD
• 1GB Kingston DDR2-800
• 2GB Kingston DDR2-667
• DVD writer
• PS/2 keyboard and mouse
• Samsung SyncMaster 753DF CRT monitor connected with VGA cable
• CPU enclosure is shoebox size with ATX PSU 400W

Eddie Ng

A: Intermittent hanging of the system, regardless of the operating system used in many do-it-yourself PC systems, is most probably due to wrong system configurations and mismatching of CPU or RAM modules.

You did not state whether you had put back the memory modules after you removed them.

According to the MSI P6NGM manual, you need to insert at least one DDR2 memory module into the DIMM1 slot before booting up the system.

DIMM1 is the slot closest to the CPU. (Note: Make sure that your motherboard is not powered up when inserting or removing hardware components and cabling since you can get an electrical shock.)

Ensure that you have fully inserted the memory modules into the slots. When correctly inserted, the two side clips will automatically move vertically to lock the memory modules in place.

Once you have made changes to the motherboard such as taking out and replacing the memory module, it is best to clear the onboard CMOS RAM information. In order to do so, locate the J1 connector just above the four Sata slots

Consisting of three pins, the jumper is connected to pins 1 and 2 by default. To reset the CMOS, remove this jumper and slot it to pins 2 and 3. After a few seconds, remove and put it back to the default position (connecting it back to pins 1 and 2).

As the CMOS information is wiped out, you need to set up all the system configurations from scratch the next time your system starts up again.

Ensure that all the wires and connectors are correctly inserted into their respective positions before powering up.

If the system still cannot boot up, check the PSU (power supply unit). It might have short-circuited when you first pulled out the components. If that is the case, you need to buy a replacement PSU.

Answer by M.K. Wong, an IT professional of nearly three decades and now a polytechnic lecturer, and Chester Chen, a recognised Microsoft Most Valuable Professional specialising in windows desktop experience.

This story was first published in The Straits Times Digital Life.

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