Thanks for the clarification.

First, how do I know if the driver list above has all drivers for my machine?
Maybe it shows only drivers which have updates.

Second, I don't have a sound card that I can see in Device Manager. Maybe it's part of something else.

Third, I can't find any motherboard support chips. How would I identify them? Which categories in the driver list?From Archives:
How do I find the computer motherboard CHIPSET?
The article has other links related to your post.
OK thanks for the link. Device manager has a line in System devices for Motherboard resources:
Device type: System devices
Manufacturer: (Standard system devices)
Location: on Intel(R) ICH8M LPC Interface Controller - 2
Driver provider: Microsoft
Driver date: 7/1/2001
Driver Version: 5.1.2600.2180
Digital Signer: Microsoft Windows Component Publisher
Conflicting device list: No conflicts.

There is no listing for Microsoft or Lenovo on the Computer motherboard links page. I guess i could contact MS for help. Or just update the driver from it's location in Device Manager.
I don't have a driver CD.

And likely there are other parts of the motherboard with other drivers. Like the MS UAA Bus Driver for HD Audio. Have to be careful with this one, I've already read about problems with its update.

Is the system mostly stable? Does the HARD drive check OK?
If so, and you have enough drive space, you  could create a small partition on the drive and do a second install of the OS. That does not violate the license.
The purpose is to see if a new install of Windows does a better job of finding suitable drivers.  It might. If not, it could mean there is a problem with the HARDWARE. This is a diagnostic trick to see if something went wrong on hate first install.

Or, a more conservative thing is tyo try and boot from a USB or CD that has a Linux Live OS. Linux does a fair job of finding drivers. Again, the objective is to see if the hardware is alright.
Just suggestions. System seems mostly stable. Main issue is the lack of any sound.
You can see my system specs in the OP.
Hard Drives: C: Total - 145744 MB, Free - 66684 MB
Disk management says C: is Healthy. I run chkdsk /r once in a while. Disk CLEANUP every day. Defrag once in a while. MBAM at least once a week.

I don't have the installation disk for XP.
Are you suggesting something like creating a new partition for a second install of XP?

I tried the Linux Cd thing but it did not work. I took out the HDD and although the Cd started, I could never get it to run Linux. Spent hours and days trying it ... several new coasters later, I don't WANT to try it again.