Computer Class

Today I held my first “computer class” with my sons Alex (15) and Zack (10).  It’s an idea I’ve been kicking around for a while.  They use the computers all the time for games, so I think it’s time they learn more about how they work.

The first thing I did was turn the computer around and talk about each of the cables going into the back: power, keyboard, mouse, network, monitor, speakers, USB (and we looked at the symbol that designates a port as USB).  Zack was interested in trying each component after unplugging the cable associated with it (except the power, which I explained to them is not good to just pull out).  I showed them what the end of each cable looks like, and had them unplug and plug them back in.  We talked a little about using this knowledge to troubleshoot problems.

Next, I brought out a computer that isn’t really working anymore so we could look inside it.  I had them remove the screw for the case and open it, then we talked about each part inside.  Taking up a lot of space are all the cables coming out of the power supply, supplying power to individual components.  I pointed out the hard drive, CD drive, motherboard, video card, sound card, network card, CMOS battery, CPU (explaining that we were looking at a fan, and underneath that fan was the heat sink, and then the CPU itself), and memory module.

I had them remove the memory module and put it back, and also remove the sound card and put that back.  Then they put the panel back on the case to close the whole thing up.  I was happy because they seemed to have a really good time.  I asked them a lot of questions as we went along to test their knowledge.  Overall, I think it was a success!

Hard Drive Paranoia

Brought my laptop running XP out of hibernation mode today and tried to start Firefox, and got some weird error about it not being able to start due to a missing file.  Tried to start something else and started seeing weirdness in other apps as well and decided to reboot.  Upon reboot, CHKDSK automatically ran and found (and seemingly fixed) a TON of errors.

I went to the Event Viewer (Start->Control Panel->Administrative Tools->Event Viewer) and could only find this error “The system failed to flush data to the transaction log. Corruption may occur.” which, after a quick Google check led me to believe it was only related to pulling out my USB drive.

I felt compelled to thoroughly check the drive before I put any more serious work onto this laptop only to risk losing it.

My idea was to copy a lot of data and then run a comparison.  First, I ran JDiskReport.  It’s a great tool for identifying what’s taking up space on your hard drive.  Using this, I located a local directory taking up about 25G.

I copied this directory to c:\testA

Then, though it might have been overkill, I copied it to c:\testB

Then I used another tool I’m liking: FreeFileSync.  This directory sync tool has a setting allowing you to compare file contents instead of just sizes and timestamps.

It took about an hour, but I compared c:\testA to c:\testB.  FreeFileSync reported no file differences.

Then, just to be safe I compared the original source directory to c:\testA.  Again, FreeFileSync reported no file differences.

Since I had done a lot of writing and reading of the hard drive I checked the Event Viewer again and found nothing scary.

From a command prompt (Start->Run->CMD[Enter]), I ran chkdsk c: .  It did do a few more fixes but it also gave me a message to the effect of “This does not indicate disk corruption”.  Still, I was a little concerned, so

I ran chkdsk /f c: .  The /F switch tells CHKDSK to fix errors on the disk if found.  It can’t run while I’m in Windows so it asks if I want to schedule it for the next boot and I answer Y.  Then I reboot.

It ran successfully, but just to be extra safe I ran chkdsk /r c: .  The /R switch tells CHKDSK to scan the entire disk for bad sectors.  Again, it can’t run while I’m in Windows so it asks if I want to schedule it for the next boot and I answer Y.  Then I reboot.

It took a long time to run (maybe a couple hours), but it ran successfully.

Checked the Event Viewer again and this time I am seeing a couple entries from yesterday in the System category which seem to indicate a problem occurred:

Warning: “An error was detected on device \Device\Harddisk0\D during a paging operation.”

Error: “A parity error was detected on \Device\Ide\iaStor0.”

Still nothing from today, though.  Guess I will keep an eye on it.