Vista VirtualPC dsl xvncviewer
From Wsms
Contents |
Vista, Virtual PC, Damn Small Linux, and xvncviewer
How to use vnc to access rop.ncc.sdccd.net unsing xvncviewer running under damn small linux installed on Microsoft Virtual PC running under Vista 64-bit edition on an AMD 64 3500+.
I did this exercise mainly for fun, but also to demonstate several points:
- Microsoft Windows Vista RC1 64-bit edition is ready for prime time.
- Microsoft Virtual PC 2007 64-bit edition actually works.
- damn small linux (dsl) is fun and can do useful work.
- You can access a vncserver on rop.ncc.sdccd.net from linux
Hardware Heck
I'll start with the hardware. Several months ago I purchased an AMD 64 3500+, an ESC RS482 motherboard (mistake) and a gig of RAM on sale from Frys. I installed the components in a case I had purchased earlier and cannabalized a hard drive and a CD-ROM reader from a machine that had fallen into disuse. The silly thing never worked right. It wouldn't shut down or restart properly and would freeze up randomly. I figured the 64-bit editions of the Linux distributions I was using didn't have properly debugged drivers for the relitively new hardware. The icing on the cake was that the Linux drivers for the on-board ATI Radeon X200 would not work properly. I had to manually edit /etc/X11/xorg.conf and disable all hardware acceleration.
What I should have done was return everything and demand my money back. What I did was to flagellate myself (just a little) for violating my rule of buying only trailing-edge hardware. Then I stuck the system under my desk and forgot about it for a few months.
The impetus to attack the problem again came when I attended a Windows Vista presentation where I was given a pre-release version of Vista in both 32-bit and 64-bit variations. Vista comes on DVD, and not on CD, so this was a good excuse to buy a DVD-RW drive and Frys conveniently happened to have one on sale.
I replaced the CD-RW drive with the brand new DVD drive. Guess what? Vista had most of the same problems that I observed with Linux distrubutions.
The next step was to look carefully at the hardware. First, I found that I hadn't seated the heat sink correctly on the CPU, which was causing the CPU to overheat. I fixed that, but the system would still freeze and crash, albeit not quite as often. I decided that I must have fried the CPU when it overheated and proceeded to test my hypothesis with memtest.
memtest
If you don't know about memtest, it is time to learn. Memtest, or memtest86 as it is properly known, is a small stand-alone diagonostic program you can run at boot time. Visit http://www.memtest86.com for all the details. Memtest allows you to boot your machine and immediately launch a very through test of your machine's RAM. Of necessity, while memtest is throughtly testing your machine's RAM, it is also testing your CPU and motherboard. In the old days, we used to make a bootable floppy to run memtest. At present, the most convenient way to get memtest is to use it from a bootable CD or DVD such as Knoppix, which is downloadable as an iso from http://torrent.unix-ag.uni-kl.de/.
When you boot your machine from the Knoppix DVD, you get a prompt where you specify the boot kernel and other options. If you type memtest at the boot brompt of Knoppix, you (surprise!) get memtest. Well, my machine failed memtest. But which component was a fault? Was it the RAM, the motherboard, or the CPU. Or, maybe more than one component had a problem.
The next step was to pull the RAM out and test it in a computer that had been working for some time. It turned out that the RAM was bad. Fortunately, the RAM was from Kingston and came with a lifetime warranty. A comple of short phone calls was all it took to get the RAM replaced.
OK. New RAM. CPU heatsync properly seated. Now it will work. Right? Wrong! It was almost as bad as ever.
What other hardware was bad?
At this point my system worked well enough to get through an install of an operating system, either Linux or Vista. But, when it booted from the hard disk it would work for a few minutes and then konk out. Aha! The hard disk. Not a problem, I had a spare. I swaped out the hard disk with a known good one, but the bad behavior didn't go away. If anything, it actually got worse.
The next step was something I should have thought of a lot earlier. When my favorite operating system (that would be Linux) runs into trouble, it writes a little note in /var/log/messages. If you look a /var/log/messages you can sometimes figure out what is wrong with your system. Of coure, I didn't think of that myself. I had to cart my computer down to the Kernel-Panic installfest and get a little help form Jim Sacks. See http://kernel-panic.org if you want some expert advice or help with linux. It's free.
Jim and I booted my PC using a Knoppix DVD and looked at /var/log/messages which had been written by my Linux install before it headed south. The last part of the file was a few dozen messages about DMA errors when accessing the hard diks. A clue! Next, Jim showed me how to use the hdparm program to turn off DMA in Linux. Now my machine finally worked. But, without DMA it was slower than sh... Well, let's just say it was really, really slow.
Try a SATA drive?
So far I had fixed two problems and isolated a third. I seated the heatsink correctly to correct the problem of the CPU overheating. I replaced the defective RAM. The third problem was that the IDE interface on the motherboard didn't get along with DMA with either of the two hard disks I had available for testing. I could try replacing the motherboard, but that would be expensive and time consuming. I could try yet another hard drive, but I didn't expect to have any better luck with the third than I'd had with the first two. I chose a third approach. The motherboard, being a relitively new model, sports a SATA interface. I decided to buy a new SATA drive and try it.
The new SATA drive didn't work at all. The BIOS would even recognize it. So, I tried the SATA drive in a different computer. Same result. Grrr...
I took the SATA drive back and exchanged it for a different one. Bingo! Everything worked. All it took was an new DVD drive, reseating the CPU, replacing the memory, and tossing out the IDE drive in favor of a SATA drive which involved about $200, two phone calls, several trips to Frys and two trips to the UPS shipping center. If there is a moral here, it must be to make sure hardware works correctly soon after you buy it. Also, you shouldn't get so excited about getting faster fancy new hardware that you waste a lot of time and money getting it to work.
