pcns - blog - eric braun, owner.








august 2006 - firecrackers in your pc?


Systemboard suffers from Capacitor Plague

If while running your PC and you hear a loud snap or bang (yet the PC continues to run) you may have a System board with a bad batch of electrolytic capacitors.  Coined the "Capacitor Plague," its initial roots were caused by industrial espionage gone bad.  More {here}.  If this happens to your Computer, it is critical to shut off your PC and call for professional help, to get options.  In rare instances the system board can catch on fire!

Panasonic 2.4 Ghz Gigarange Cordless Phone Blows away Wireless Network

Referencing my Zap checker at the noise threshold of 20%, about 15 feet away from the Wireless router. With the customer out front talking on a 2.4 ghz Panasonic Gigarange Cordless phone, it pegged my Zap checker. She said she can get 1/4 mile range walking down the street. Their complaint? The wireless network in which the laptop is connected drops out completely when they answer calls with the panasonic cordless. That Panasonic unit literally blasts a signal and rubs the Wireless out of existence. The customer will try different wireless channels.

July 2006 - Intel D915GLVG Works for a while, then Quits

A customer's Intel mobo, micro-atx Socket LGA775 with 2.6 Ghz Celeron. About 80% of the time it would run okay, but as described by customer would run okay then simply stop working after three days. No boot, just a blank stuck POST screen, sometimes a blank screen. I took it back to the shop. I put my reboot program on it to exercise it. After about 8 times it simply stopped at the post screen and hang, sometimes it would make it to windows. Intel Desktop software monitoring, which runs on windows, monitors all hard drives, cpu temp, and power supply voltages would refuse to shut down, after each reboot.

Ok, so I think I found the problem. The PC builder installed a media adapter, which composed of a USB, Firewire, various memory card/stick slots. You've seen these things, they go into a 3.5" floppy drive bay, and they plug directly into the motherboard.

The original system builder had the Firewire 10 pin header (actually only 9 pins are used) plugged into the system board header for the USB port - he was actually bridging two usb ports into the single firewire connector. This was probably stressing the usb port, perhaps the power supply somewhat, and perhaps it was causing the Intel software monitor to hang up.

Well with this impediment removed, it's successfully rebooted for over 2 days, 24 hours a day now, that's the longest it's ever lasted - with that plug inserted, the best it could do was about 30 minutes before it stopped working.

Here's the 9 pin header output of a firewire connector:

{http://www.interfacebus.com/Design_Connector_Firewire.html}

The Firewire twisted pair b minus connected to VCC of usb, and VCC of 2nd usb connected to twisted pair b Plus of USB.  Firewire pins 5 and 6 are grounds so he had the D+ leads of both USB ports grounded. That couldn't be good.

Biostar Motherboard randomly Blue Screens

This was their Intel Socket LGA775 series - a P4M800-M7a-rev 7.0.  Something to watch - those LGA775 CPU coolers, watch that the system builder inserted all nylon inserts fully, and the center plastic pin is locked down. One of the legs wasn't, so the CPU cooler may have not been making good solid contact with the Intel Processor.  I replaced it with a Solid Copper Cooling Master Cooling Pipe CPU Cooler. This has a insulated Steel Bracket which goes on the bottom side of the Mobo, and is held in with screws not nylon snaps, which holds the heat sink much more securely. It keeps the CPU about 18 to 20 degrees cooler than the stock Intel CPU Fan.

This is the $50 {Cooler Master Hyper 48} which has multiple brackets for both Intel and AMD processors.  Beware, this cooler is over twice the weight recommend by both AMD and Intel.  This means if you plan on moving or shipping the PC the heat sink should be removed, because the weight of the heat sink may damage the systemboard while in transport.

June 2006 - Spamblocker prevents Outlook Express from Sending E-Mail, VPN Connectivity Issues.

     Spamblocker, from spamblocker.com, when upgrading from 4.2.0 to 4.2.4 (using automatic updates) can cause Outlook Express (and Outlook) to stop sending E-Mails.  Quoting from the website, "We are very sorry for the inconvenience."

     Had a customer with an office to office (firewall appliance hardware VPN).  They couldn't access the remote Server across the VPN, yet users at the remote office could access the main server back to the main Dallas office.  In this case, the remote Server was nothing more than a Windows XP Professional computer.  Solution was to expand the scope of the Windows XP Firewall.  Go to Windows Firewall, click the Exceptions tab, click file and print sharing, click properties, click Edit, add the subnet scope of the Dallas office in the remote office, in the format 192.168.1.0/255.255.255.0 (the Remote office subnet), 192.168.2.1/255.255.255.0 (the Dallas Office).  Whenever there's a case of only one-way communication, always suspect the firewall.