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eMachines 820 Trigem Alaska 3 Mobo Dead

Posted: Fri Feb 16, 2007 5:00 pm
by JEWilson
Magna 600W ATX 20 pin PSU
Board Dead - no cpu fan
PSU Fans spin up ok

Keybard LEDs flash intermittently that is Caps lock, Scroll and Number lock. Mobo Front Panel switch does not switch on the mobo.

No activity on POST CARD seven segment display but
POST Card LEDs report;
Sys - Flashes
Clk - On
I/O W - Off
Osc Frame - Flashes
Reset - Flashes
BIOS Rdy - Off
Data - Off
-12V - On
+12V - On
-5V (3.3V) - Flashes
+5V - On (Flashes)

After 5-10 minutes, Keyboard LEDS stop flashing and
POST Card seven segment LEDs still nothing
The POST card LEDS report;
Sys - Flashes
Clk - Flashes
I/O W - Off
Osc Frame - Flashes
Reset - Flashes
BIOS Rdy - Off
Data - Off
-12V - On
+12V - On
-5V (3.3V) - Flashes
+5V - Flashes definetly as compared to the prior instance

I figure the 5 volt rail is problematic given the time frame probably
bad caps going s/c.

Any other suggestions?

Posted: Thu Feb 22, 2007 12:54 am
by edwin
keyboard leds flash intermittently like a walking light? Never seen that before. Tried hotflashing the bios chip with a proper bios file?

Posted: Mon Feb 26, 2007 1:50 am
by JEWilson
Yeah - flash intermittently.

BIOS device soldered to board.

Q - I have a Willem but was of the opinion the device would have
to be removed prior to reading the BIOS image or re/hot flashing.
I have seen advice some of the low voltage flash pieces such as with 5V and 3.3V can be read/flashed in situ.

Would you agree?

I believe (old) BIOS devices requiring pp 12V or greater might harm ICs
where erased or written in situ.

Posted: Mon Feb 26, 2007 8:21 am
by edwin
What is the part number of the bios device? We might try and find out what voltage it wants.

Posted: Wed Feb 28, 2007 12:34 am
by JEWilson
The part is a FWH/LPC type, an Atmel AT49LH004

http://pdf1.alldatasheet.com/datasheet- ... LH004.html?

These only require 3.3V

Posted: Wed Feb 28, 2007 1:04 am
by cp
you can try to flash it in place with nothing else in the board. the power supply shouldn't do anything to other devices.

Posted: Wed Feb 28, 2007 3:38 am
by JEWilson
I would like to get an image from it by reading it first.
As I do not yet know the OEM for this mobo but suspect it is eMachines, to do this first is priority. This depends of course on the fact, if the board is dead becuase of a prior bad flash - reading the image would be no use.

I believe I require an adapter for the willem to facilitate this.
Can someone point me in the correct direction or would it be easier
to make one?

Posted: Wed Feb 28, 2007 11:04 am
by cp
if you're smart enough: build your own. get a plcc carrier and put if upside down on the bios chip. smd plcc carriers are smaller so they might not interfere with surrounding parts but ofcourse they are a lot harder to handle in terms of soldering.
if you attach a wire to the programmer's side of the adapter make sure its length doesn't exceed a few centimeters. else you will end up having parasitic capacitances and inductances.

Posted: Sat Mar 10, 2007 2:36 am
by JEWilson
Hi,

RE - reading and flashing in place

You state this can be done where no other peripherals are in
expansion (PCI, AGP) slots, no CPU is installed, no drives are
installed and no PSU attached to the system.

Are you sure a read/write in this manner will not damage the mobo?

Whereas I conceive damage might occur with historical pp voltages
as were/are required for old devices such as 12v and 25v etc,
I suspect with new generation flash devices at 5v or more likely 3.3v,
these will not.

But I do not want to damage the mobo if I can help it.
Any suggestions or advice?