Posts

Posted on

Testing RAM

You should test new RAM to make sure that it works. You should also test existing RAM when your computer is acting weird. Computer RAM does go bad. When it does, you can see erratic behaviors such as computer freezes, incorrect screen drawings, and corrupted files. Most people assume that this is due to a virus.

A few years ago I saw a manager in a Reston, Virginia office reprimand an employee because the manager assumed that the employee somehow infected a computer with a virus. The important computer documents had been corrupted and could no longer be opened. We figured out later that the real culprit was just bad RAM that had incorrectly written the files to disk.

Testing RAM on a PC

Using a bootable CD such as Ubuntu or the Ultimate Boot CD as described in my Live CDs post will allow you to run utilities to test PC RAM.

Testing RAM on a Mac

Thanks to command-tab.com for creating a utility for thoroughly testing RAM on a Mac computer. Run their install package, shut down the computer, boot up while pressing the Command and S keys (to go into Single User mode), then type memtest all 2 in order to run the memory test twice.

I recently ran this test after adding more RAM to a computer for a Washington D.C. customer.  The test showed that the new RAM had no problems.

Posted on

Google Chrome Browser First Impressions

Today, Google has launched their own browser called Chrome.  There’s no doubt Google is trying to control all things on the web and this is yet another step towards that goal.  Their search engine is dominant and they’ve been trying to push online applications such as Google Docs.  By creating their own browser, they can more tightly integrate their web applications with the browser.  

Speed

The first thing I noticed when trying out Google Chrome was the speed.  It felt very fast to me so I ran some simple speed tests trying to render amazon.com using the latest Firefox and Safari.  Firefox and Safari were very similar taking slightly less than 5 seconds.  Chrome did the same site in less than 3 seconds.  There’s no doubt it is a fast browser.  Google claims it has the fastest javascript engine which may be the reason it loads faster than the other browsers.

Bookmarks?

Chrome tries to simplify their browser.  The end result is the default has no visible bookmarks, menus, or even a button to add bookmarks.  Type something in the address bar like “firef” and it will list the Firefox site that you can arrow down and select.  It does this even if you’ve never been there before so the browser has some intelligence about where you might be trying to go.  It is as if Google is saying bookmarks aren’t necessary.  Another feature saying you don’t need bookmarks is the most visited page which is the default page shown when you load.  It displays the 9 pages you visit most with thumbnails of each displayed so you’re one simple click away from your most favorite sites.  You can add a bookmarks toolbar but there is no menu of any kind.

Mac? Linux?

I expected Chrome to be lame and pointless since there are already several good browsers out there.  But its speed has impressed me and makes me want to see more.  Unfortunately, they have not released Chrome on Mac or Linux yet.  I’m sure they eventually will but it could be a while.

Endgame

Google recently extended their deal with Mozilla, makers of Firefox, until 2011.  Google pays Firefox to have google.com be the default search.  But what will happen then when Google no longer needs Firefox to point to their search?

Posted on

Encryption on USB Flash Drives

USB Flash Memory Drives have become the replacement of the floppy disk.  You can get a 16GB flash drive for around $50 so they offer a great backup and travel option.  But what if you have your important data on it and you lose it?  Then whoever finds it will have easy access to all your data.  That’s why encrypting your data on a flash drive is so important.

Mac OS X Disk Utility

Some operating systems like Mac OS X have built in features to create encrypted volumes.  This can be done through disk utility.  You create a file of whatever size you want and that becomes a new mountable volume once you double click it and enter your password.  Without the password, you just see a single file that you can do nothing with.  This is a great option for Mac OS X but then if you find you need to access your files on Windows or Linux, you are out of luck.

TrueCrypt

The best multi-OS solution is TrueCrypt.  You can download versions of TrueCrypt for Windows, Mac OS X, and Linux.  You should then copy each of these versions to your flash drive.  Then you can run the appropriate version on whatever OS you are on.  With TrueCrypt, you can create an encrypted file of whatever size you want. Within the program, you can then select the file to mount it as an accessible drive.  In Windows, that means you’ll assign it to a drive letter.  On Mac or Linux, you should see the volume appear on your desktop.  Then use it like you would any other volume.  When you are done, you can unmount it and remove the flash drive.  

It does take these few extra steps of mounting your volume to get to your data but it is well worth the ability to access your encrypted data from any OS.  If your data is at all sensitive, you should definitely consider using TrueCrypt.

Posted on

Easy Webcam Setup with Ustream

A friend who fled New Orleans and Luling, Louisiana showed me his webcast on Ustream. Ustream allows Mac and Windows users to share their video on a Ustream page. Unlike broadcasting a live feed straight from your computer, Ustream can handle thousands of visits, as my friend’s page had before his house lost power when hurricane Gustav hit Louisiana this morning.

Another service like Ustream is Stickam. Both are free so I suppose their business model is to just be purchased by Google.

If you have a webcam and a nice view from your window, give Ustream a try. Or you can just use it to watch emergencies like this.

Best of luck to everyone in the storm.

Posted on

iPhone Special Diagnostic Codes

Thanks to AppleGuy Tom for providing these codes which work on most US AT&T phones and have been tested on the iPhone. Simply type these codes as if you are calling them.

*3001#12345#* -Displays the Field Test Mode, network, cell, GPRS, call, and version information.

This picture shows the information from one of my cell towers. The Rx Level is showing the signal strength from that particular cell. Note that in Field Test Mode the signal meter in the top left corner changes from a 5 bar readout to a number. This is more accurate and can help when placing your antenna for a signal booster, for example.

*#06# -Displays the 15 digit IMEI (International Mobile Equipment Identity) in the middle of the screen. (This number is also printed on the back of the iPhone.)
This number is worth writing down. Your carrier can deactivate the phone with this number so that it will not work if ever lost or stolen, even when using another SIM card.

*#21# Displays ‘forwarding’ state (enabled or disabled) voice call, data, fax, SMS, sync data, Async data, packet access, and pad access forwarding for outgoing calls.

*#30# -Displays ‘Caller ID’ (enabled or disabled).

*#33# -Displays ‘barring’ state (enabled or disabled) voice call, data, fax, SMS, sync data, Async data, packet access, and pad access forwarding for outgoing calls.

*#43# -Displays ‘call waiting’ state (enabled or disabled) voice call, data, fax, SMS, sync data, Async data, packet access, and pad access forwarding for outgoing calls.

*#61# -Displays ‘call forwarding to voicemail’ state (enabled or disabled) [and number forwarded to] of voice call, data, fax, SMS, sync data, Async data, packet access, and pad access forwarding for outgoing calls.

To change the number of seconds before the call forwards to voicemail, retrieve your eleven digit number from *#61# then carefully type *61*numberRetrieved*11*30# -those last two digits are the seconds to ring (Default is 20; Max = 30)

*#62# -Displays ‘call forwarding when unreachable’ state (enabled or disabled) [and number forwarded to] of voice call, data, fax, SMS, sync data, Async data, packet access, and pad access forwarding for outgoing calls.

*#67# -Displays ‘call forwarding when busy’ state (enabled or disabled) [and number forwarded to] of voice call, data, fax, SMS, sync data, Async data, packet access, and pad access forwarding for outgoing calls.

*225# -Requests an SMS message displaying the current monthly balance. (if applicable)

*646# -Requests an SMS message displaying the remaining monthly minutes. (if applicable)

*777# -Requests an SMS message displaying the pre-paid account balance. (if applicable)

Some other AT&T codes currently do NOT work on the iPhone: *#4720# (voice quality reduction codec -to save battery) and  *3370# (better voice quality codec)