Netgear AC750 Wifi Range Extender (EX3700)
Hard disk suspension in an Antec SLK3000B
The main problem of the Antec SLK3000B case is it converts hard disk vibrations to noise, and this is the most annoying noise coming from my pc when the fans are set at the lowest speed. In the SLK3000B the hard disks lay in a cage with grommets that are supposed to dampen the vibrations of the 7200 and more rpm hard disks.
The trend spreading amongst silencing modders is to suspend the hard disks in the air to avoid contact between the case and the hard disks.
Recover "Logical sector size is 0" with dd
A few hours ago while I was using my pc suddenly Windows froze completely (mouse was stuck and Ctrl+Alt+Del did nothing). It's not astonishing but I was quite surprised because such a freeze never happened since I began using Windows XP on my new pc.
The problem appeared at the reboot:
grub, the bootloader on /dev/sda, showed this error message:
At reboot I started Windows XP Recovery Console from the Windows CD and tried
CHKDSK.EXE, and this was the outcome:
I booted again linux to launch
fsckand see it fail:
Then I found the solution in ubuntu forum:
root@am2:/home/z24# dd if=/dev/hda1 of=/defmedia/bkup_fat32_hda1.img bs=512 count=2048000 conv=noerror,sync 2048000+0 records in 2048000+0 records out 1048576000 bytes (1.0 GB) copied, 43.61 seconds, 24.0 MB/s root@am2:/home/z24# dd if=/defmedia/bkup_fat32_hda1.img of=/home/z24/sector6.bin bs=512 count=1 skip=6 conv=noerror,sync 1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.011544 seconds, 44.4 kB/s root@am2:/home/z24# dd if=/home/z24/sector6.bin of=/dev/hda1 bs=512 count=1 conv=noerror,sync,notrunc 1+0 records in 1+0 records out 512 bytes (512 B) copied, 0.030644 seconds, 16.7 kB/sExplanation:
- the first dd makes a backup of the first gigabyte of the Windows partition: I copied 1 GB only because I didn't have enough space on a ext2fs to backup all the 28 GB of /dev/hda1.
- the second dd extracts the sixth sector to a temporary file: as reported by Microsoft KB247575, "The backup FAT32 boot sector is located at sector 6 of the logical drive".
- the third
ddcopies the extracted sector 6 to sector 0 of /dev/hda1.
ddwas also checked with
mount. Thanks a lot to the ubuntuforums user Onlymee for his post!
Update 13.09.2008The same problem happened again today and gave me the opportunity to complete the series of error messages :)
The first, at boot time, was the same: Mounting the partition (
mount -t vfat /dev/sda1 /mnt):
dmesg | grep sda1But
fdisk -l /dev/sdashows the partition table.
fsck.vfat /dev/sda1(executed from Ubuntu 8.04 alternate cd) The solution was exactly the same: copy the sixth sector back to the first. And voilà, it booted.
.htaccess: an example of the Apache per-directory configuration file
Using bloxsom as my weblog designing application, I had to provide some settings to the Apache
.htaccess configuration file to fine-tune the usage of my site:
- tell Apache to load
index.cgiin addition to the default
- rewrite the requested address adding
www.if it's omitted
- rewrite the requested address adding
index.cgiif it's omitted
- and for bandwidth reduction, forbid robots from crawling some pages
(Updated Aug 29 2013)
This 3Com product has many functions: router, firewall, adsl modem, wireless access point, 4 port switch. 3Com chose to give two names to its products: a name for the market (as the long name in the title), which identifies the purpose of the product and is not changed when a new model replaces the older one, and a model name, a number which identifies the specific model.
The "ADSL" term in the name is particularly useful to specify that it's a adsl modem too, with a RJ-11 port that would connect the router directly to the phone line, through a RJ-11 cable, just like any adsl modem; in fact I found several routers that were capable of routing the adsl signal but were equipped with a RJ-45 port instead of a RJ-11 port: they were not DSL modems and needed to be connected to an external DSL modem. Checking the rear of the product, maybe on the user guide, can help making sure the router is a DSL modem too.
I will review two 3Com OfficeConnect ADSL Wireless 54 Mbps 11g Firewall Router models, the older 3CRWDR100A-72 and the newer 3CRWDR101A-75.
- Reliability and 3Com assistance
- Wireless trouble with 3CRWDR101A-75
- Wireless coverage
- Other features
- Missing features
- GPS accuracy
- Connecting to internet via bluetooth phone
- Making a flat surface
- Installing - ouch, it's not compatible with some MSI K9N Platinum
Mounting a second fan on the back of the case (Antec SLK3000B)
With the summer approaching, I am making some experiments trying to cool my pc as much as possible while keeping it quiet. Now, airflow in the case is made by 2 fans: the intake fan, a Papst 4412 F/2GLL, pulls air inside the case from the front, the exhaust fan, a Antec Tricool coming with the SLK3000B, pushes air out to the back; in addition, the psu fan pulls air from the top of the motherboard through the psu to the back.
Since I bought a second Papst 4412 F/2GLL, I tried positioning this fan in different locations to see which one conributes the best to the cooling. One of these is the back of the case, in the bottom, where there would be additional cards: it pushes air out of the case through the back slots.
I'll try to answer these questions:
- What is AMD Cool'n'Quiet?
- Does it really work?
WAMP & Perl - Windows Apache, MySQL, PHP with CGI scripts written in Perl
I need Perl to run Blosxom, an open source and free CGI script to create blogs.
So I installed WAMP5 1.6.4a and ActivePerl 220.127.116.117 with MSI installer.
I already have my site on my disk, so I told my site directory to WAMP during the setup procedure and then I pointed my browser to http://localhost/index.cgi but it displayed the cgi instead of executing it.
This is what I did to make it work:
Running PHP scripts from command-line with WAMP (Windows Apache, MySQL, PHP)
On my old pc I installed Apache, MySQL and PHP singularly, and I made some PHP scripts to be runned from command-line, like this:
c:\php\php -f myscript.phpOn my new pc I installed WAMP5 1.6.4, all was running fine (phpMyAdmin, my local website, php scripts pointed to by the browser) but php scripts launched by command-line reported
Fatal error: Call to undefined function mysql_connect() in myscript.phpObviously I changed the php path to
c:\wamp\php\phpbut with no results.
Solution: change the command to
c:\wamp\php\php -c c:\wamp\apache2\bin -f myscript.phpThe -c option tells php to search php.ini in the directory specified, and that's needed because WAMP puts php.ini in Apache bin directory, while with a PHP regular installation php.ini is located in the php.exe directory.