Archive for December, 2006

Unable to connect Linux computer to Dlink DI-624 router due to ipv6

Recently, I installed Ubuntu 6.06 on an old laptop. Much to my surprise, the Dlink DWL-G650 wireless card was recognized. Much to my annoyance, the wireless did not work. Here’s what I did to fix the problem. I open up a terminal window and type iwconfig.

lo no wireless extensions.

eth0 no wireless extensions.

ath0 IEEE 802.11 ESSID:””
Mode:Managed Frequency:2.412 GHz Access Point: Not-Associated
Bit Rate:0 kb/s Tx-Power:20 dBm Sensitivity=0/3
Retry:off RTS thr:off Fragment thr:off
Power Management:off
Link Quality=0/94 Signal level=-95 dBm Noise level=-95 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

sit0 no wireless extensions.

From the result, it would appear that the drivers were found and loaded (or we won’t be getting ath0). The access point “Not-Associated” is more troubling though. I selected System->Admin->Networking and the network card and looked at the Ath0 properties. I had enter the WEP earlier, but I realized that I had enter the WEP Key in hex but set the type to ASCII. I was sending the wrong key (note that I had also set properties to use DHCP).

With the correct key, I enter iwconfig again:

lo no wireless extensions.

eth0 no wireless extensions.

ath0 IEEE 802.11g ESSID:”Literbox”
Mode:Managed Frequency:2.422 GHz Access Point: 00:12:59:19:17:5E
Bit Rate:48 Mb/s Tx-Power:18 dBm Sensitivity=0/3
Retry:off RTS thr:off Fragment thr:off
Power Management:off
Link Quality=13/94 Signal level=-82 dBm Noise level=-95 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

sit0 no wireless extensions.

Now notice the access point’s MAC address is returned. However, the wireless is still not working. I did a dmesg and see the following error message:

[17179906.596000] ath0: no IPv6 routers present
[17179931.316000] ath0: no IPv6 routers present

So what seems that the router a Dlink DI-624 Rev C is not compatible with IPv6 protocol. I am assuming this because I can’t find any info on the Dlink website, but some site indicated that DI-624 Rev D handled ipv6. In any case, this mean I have to turn off ipv6. Follow the instruction on this link to disable ipv6.


December 28, 2006 at 3:17 am Leave a comment

Grub hangs on boot up due to BIOS

After I install Ubuntu on an old laptop. It worked for a few hours and then failed to work after a reboot. All I get on screen was:

Grub Loading Stage 1.5

What in the world happen? Nothing was changed and now it’s broken. I managed to boot off a floppy and took a look at the partition and it looked OK. After an hour of fiddling with it, I decided to just reinstall. First I boot off a Windows ME startup disk and did:

fdisk /mbr

This restored the windows MBR so I can boot into windows. Everything was working under windows. I even did a scandisk and it found no errors. I decided to run Instlux again to reinstall. This time when I boot up the machine, I only got a message that grub is loading and then nothing.

hockeyman_102 on suggested that it was a BIOS or Hard disk problem. I was pretty sure it was not a hard disk problem, but I have never had a BIOS related issue before. I tried to going into the BIOS and select save. No dice. Finally, I selected the option to reload factory setting and everything was fixed.  I still have no idea what caused the BIOS to flake out in the first place.

December 28, 2006 at 2:25 am 1 comment

Using Instlux to install Ubuntu in windows XP over the network

Recently, I purchased a new computer for my fiancee. This left her old ancient Toshiba 1805-S207 for me to experiment on. The problem is that the CD-ROM has died (it returns IDE #1 error on startup), so I can’t install from CD-ROM. It’s an old machine, so it can boot from floppy, PXE, PCMCIA hard disk, but not from usb.

I attempted to set up a PXE server, but I was only partially successful. I found this program call instlux which allow installation from Windows. It however does not come with a lot of instructions, so I write down my experience.

Instlux comes with several different types:

  • Instlux
  • Instlux for Ubuntu
  • Instlux for Suse

The Instlux is the base installer which allows you to install from many different Linux distro, but requires configuration. The other instlux is preconfigure to work with a single distro. The Ubuntu installer comes in a version from CD-ROM and one that install from network. The Suse installer only installs from CD-ROM. Since I don’t have a CD-ROM, Ubuntu network installer was the easiest way to go. If you have a working CD-ROM and can’t boot from it, I recommend using Smart Boot Manager to boot from a floppy and then use that to boot from the CD.

To use Instlux, follow the following instructions:

  1. Make sure you back up your drive! I did not encountered any problems during installation, but one person on the net trashed his hard disk. Remember that you have to repartition your hard disk, so data loss is always a possibility.
  2. Download Instlux from the Sourceforge site. In my case, I download the english version of Instlux for Ubuntu network. As of this writing, Instlux only support install of Ubuntu 6.06.
  3. Run the installer. This installs the installer into the C: drive and modify the c:\boot.ini file (which is normally hidden in Windows). The installer consists of the instlux directory with custom vmlinux and initrd. There is also a glrdr that calls the Ubuntu installer. The installer will prompt you to reboot. Note that if you are using Windows 98 or ME or earlier, Instlux won’t work without some configuration because ME or earlier does not use the same boot loader as NT.
  4. Reboot the computer, pay attention at this point. You will get a menu that allow you to select Windows and Ubuntu 6.06 installer. Select the Ubuntu installer and press enter. The menu appears only for a few seconds. If you don’t pay attention, it will boot into Windows by default and you will be prompted to uninstall Instlux and be confused like I was. If you get a prompt to uninstall instlux. Reboot the machine and pay more attention to the screen.
  5. When you select the installer, glrdr is loaded and you get an option to install Ubuntu 6.06. You can follow the instruction to install Ubuntu 6.06. Be careful when you get to the section where it asks if you want to installer over your hard disk if you want to dual boot your machine.
  6. Installation took hours. I am not sure if this is because I was running this on a 1.1 Ghz Celeron Coppermine or if it’s because I was install Ubuntu over a 768K DSL instead of a faster CD-ROM drive.
  7. After the install, I boot into Ubuntu and got a strange drumming noise that slowly faded away as the computer run. Weird! It never happen again after a reboot. Everything worked fine. Even the wireless driver for the DWL-G650 card was installed. Unfortunately, wireless connection did not work, but it appears that it was because my router does not support ipv6.
  8. I reboot into windows and got the promp to uninstall Instlux. This time, I click yes and it remove Instlux and restore the boot.ini file.

Now I can dual boot into windows or Ubuntu.

December 25, 2006 at 4:15 pm 2 comments

Super PI Score on Different Computers

Here’s a list of Super PI score (2M) on different computers I have access to:

Computer SuperPI 2M Score (min) Idle Temp (C) Full Load Temp
Acer Aspire 3680. Celeron M 520 (1.6 Ghz) 512 Mb Vista 2:19
Acer Aspire 3680. Celeron M 520 (1.6 Ghz) 2 Gb (dual channel) Vista in Vmware 1:43
Acer Aspire 3680. Celeron M 520 (1.6 Ghz) 2 Gb (dual channel) Vista 1:39 57 65
ASUS eee 901 Intel Celeron M 900Mhz Windows XP 3:22
ASUS UL50 Intel Core 2 Duo SU7300 1.3G 1:06
Averatec 2370. Turion64 TL-50 (1.66 Ghz) Single RAM Module 2:06 45 70
Averatec 2370. Turion64 TL-50 (1.66 Ghz) Two RAM Module 2:06 45 70
Compaq 906us. Athlon XPM 1500+ (1.3 Ghz) 3:26
Custom Desktop. Athlon XPM 2600 (2.0 Ghz) 2:12
Custom Desktop. Athlon II X4 640 (3.00 Ghz) 1:01
Dell e1505. Core Duo T2250 (1.73 Ghz). Single RAM Module 1:37 50 65
Dell e1505. Core Duo T2250 (1.73 Ghz). Dual RAM Module 1:28 50 65
Dell Latitude D630 (2.4 Ghz Core 2 Duo T8300) 0:52
Dell Inpiron 4150 (1.7 Ghz Pentium 4 M) 3:51
Dell Inspiron 9300 (2.0 Ghz Pentium M) 1:45
eMachine T1221. Celeron Tualatin (1.3 Gz) 7:08
MSI Wind. Intel Atom N270 1.6 Ghz Windows XP 3:32
HP Pavilion dv5-1150us Intel Core2Duo P7350 2.00 Ghz 1:00
IBM NetVista. Pentium 4 (1.8 Ghz) 4:00
IBM NetVista. Pentium 4 (2.4 Ghz) 2:52
Toshiba 1805-S20. Celeron Coppermine (1.1 Ghz) 9:28
Toshiba Satellite C655-S5047 Celeron 900 (2.2 Ghz) Windows 7 64-bit 1:04

Both Turion64 and Core 2 Duo supposedly gain improvement through a matched pair of RAM, but apparently there’s no difference in performance in Turion and only a small gain in the Core 2 Duo. All benchmark and temperature ran under Windows XP unless otherwise specified.

December 12, 2006 at 4:10 pm 2 comments

Intel Core Duo T2250 vs. Turion64x2 TL-50

Recently, I gotten my fiancee a Dell e1505 with a T2250 and I got myself a Averatec 2370 with a TL-50. I was curious to see what the difference in performance and temperature the two processors were. I first check the temperature of the two processor at idle and underload.

CPU Idle Full Load
Intel Core Duo T2250 50C 60C
AMD Turion64x2 TL-50 45C 70C

This sort of make sense, reviewers indicated that the Turion64 has lower power than the Core Duo on idle, but uses higher power under load. Of course, it could also mean that the e1505 has a better cooling system than the Averatec 2370.

I ran Super PI and here are the results.

CPU Max Frequency (Ghz) Super PI 2M Score (min. Lower is better)
Intel Core Duo T2250 1.73 1:37
AMD Turion64x2 TL-50 1.6 2:06

It appears that Core Duo is faster than the Turion at least in Super PI. I’ll do further test when I have a chance.

December 11, 2006 at 4:09 am 1 comment

Undervolting Averatec 2370 (Turion64x2) using RMClock

Recently, I purchased an Averatec 2370 laptop with Turion64 x2 TL-50. I wondered if I could use RMclock to underclock and undervolt the Turion64 and what sort of effect it will have on the temperature and battery times.

First, I had to find out the Turioni64 x2 TL-50’s frequency and voltage range. I tried reading the literature on the AMD site, but it was hopelessly out of date. The white paper on the thermal characteristic is dated back to March 2006.

I launch RMClock and set it to monitor the voltage and frequency. I then open the Window’s Power Options object in Control Panel and set it to the following entry to “Always On”, which sets the computer to the highest frequency and voltage. I then set the power to “Max Battery”, which displays the lowest frequency and lowest voltage.

Configuration Frequency (Ghz) Voltage (V)
Minimum Power 0.804 0.800
Maximum Power 1.607 1.075

With that in mind, I ran RmClock, set the management to use Power Saving and set it to the smallest multiplier and voltage to 0.8V. I then ran CPU Burn and keep lowering the voltage. I managed to get it to below 0.700V before the computer crashed. I then set the management to Maximal performance and set it to the highest multiplier and the voltage of 1.075 v. I then keep lowering the voltage while running CPU Burn until the computer crash. I manage to get the voltage down to below 0.875V before the computer crashed. Finally, I set the management to Performance on Demand. I selected all of the multiplier and set the min and max voltage to the voltage to 0.700 V and 0.875 V. RmClock then adjust the immediate voltage from between low and high multiplier. Even though CPU Burn indicated a usable range of 0.7 – 0.875 v, the computer crashed when I attempted to install at 0.7 v. I upped the low end voltage to 0.712 v and the problem went away.

When I set management to “Performance On Demand”, the computer crashed. It turned out that half-step transitions is not allowed. Make sure you have the option unchecked in the Advance CPU Settings, P-Transitions Tab.

I then ran a test where I ran two copies of CPU-Burn (since we have two core, I needed to run 2 programs to get 100% cpu usage) and with wireless off. The computer is set to ran at the highest speed possible. The only difference between normal and undervolt is that normal runs at the default voltage of 1.075v while undervolt ran at the lower voltage of 0.875 v.

Configuration CPU Freq (Ghz) CPU Voltage (V) Battery Life (hours) CPU Temperature (C)
Normal 1.6 1.075 0:49 70
Undervolt 1.6 0.875 1:12 56

I was surprised by how much the temperature dropped when I reduced the voltage by 0.2 volts. By undervolting, one can extend battery life, reduce heat, while getting the same performance. This is a free lunch.

Undervolting potential will vary from chip to chip, so you’ll have to experiment to see how low you can go.

December 3, 2006 at 2:28 am 1 comment


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