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Maggi
9th June 2005, 09:54
Hi Peeps'n'Geeks,

here at work, one of our Tyan Thunder K7 stopped working altogether.

I tried basically everything to troubleshoot, ie. ripped out all components, incl. CPU & RAM, PSU etc. and replugged everything bit by bit, while trying to power it up between each step of dis- and re-assembling.

The only visible sign of life is a short blinking of it's onboard NIC LEDs when physically hooking up the PSUs main power chord, after that nothing happens ... no beeps, no ever so slight fan movement, nothing at all ...

I even shuffled CPUs back and forth, ie. both MP2400+ as single CPU setup in CPU slot 1, both CPUs in dual setup with change of slots and even dug out our olden MP1200 CPUs and tried those in single and dualmode.

Still dead silent.

Consequently, I suspected the mainboard being broken for whatever reason and ordered as replacement board a Tiger MPX, that is also supposed to support our CPUs and believe it or not, this new board shows exactly the same behaviour, ie. it stays dead silent when trying to power it up.

Now I'm completely lost what the real problem could be and would like you folks to give me a few ideas about what the problem could be and/or how to nail it down further.

TIA for any pointers, hints and ideas !

GT98
9th June 2005, 10:57
Change out the PS?

Wombat
9th June 2005, 11:02
Get a voltage meter on your PSU rails. It's easy to short the ATX turn-on wire so that it will power up without a motherboard.

Maggi
9th June 2005, 11:05
GT98:
I tested the original PSU in another system and it was fine, I also tested a new PSU in the suspect system and it stayed dead

Wombat:
could you give a few more details on how to start a PSU without having a mainboard connected ?

Thanx so far, guys !

GT98
9th June 2005, 11:09
GT98:
I tested the original PSU in another system and it was fine, I also tested a new PSU in the suspect system and it stayed dead

Wombat:
could you give a few more details on how to start a PSU without having a mainboard connected ?

Thanx so far, guys !


I know you need a resistor for an ATX power supply....dont recall how to get it powered up though...I'm sure that you can find something on the net.

found this:

http://www.duxcw.com/faq/ps/ps4.htm

Another
http://www.fonerbooks.com/power.htm

az
9th June 2005, 12:18
Make sure you are not acidentally shorting it by running it on the bag it came in, etc.

AZ

Kurt
9th June 2005, 14:39
could it be a power plug/cable problem? have you tried it at another location/room?

Fluff
9th June 2005, 16:14
Did you try each piece of memory one at a time. That happened on guy at works system (a Tiger MP). Got beeping for a while. Subsequently went dead. It was a strange problem.

UtwigMU
9th June 2005, 18:57
Tyan has 3 year warranty and they answer tech support mail, just send a mail to adress provided in automated reply to hear from real person.

Otherwise TigerMPX issues I noticed:
- If you change any card the board will need a CMOS reset in order to post. When you clear and replug cmos jumper and plug in PSU it boots right up, so make sure coolers are on processors and board is clear to start.
- Sometimes motherboard monitor sensors reset to 0. You need to turn off/unplug PSU for a while in order to post.

You can also try the board with regular XP processors (supports also bartons, but XPs will work only as single CPUs).

VJ
10th June 2005, 01:00
Check to see that the reset button isn't stuck...

I had this problem once (key was stuck underneath the cover of the key), and it took quite some time find out that this was causing it...


Jörg

Maggi
10th June 2005, 03:07
Thanx for the pointers guys !

- CMOS was cleared before I started dis- and re-assembling
- the antistatic bag is far away when plugging in the powerchords
- I tried two PSUs that both run fine in another system
- in the moment there's no RAM stick installed (I'm waiting for beep codes)
- Tyan's Tech support is crap, I'm trying to get answers and/or solutions for another problem (http://forums.murc.ws/showthread.php?t=53025) for quite some time now
- so far I tested two MP2400+ and two MP1200 in all possible combinations (except for mixing speeds of course)
- I also tried both FSB speeds
- there are two boards showing the exact same behaviour, a Thunder K7 and a Tiger MPX
- a stuck reset switch cannot be a problem, since it's not even connected

Question 1:

If the mainboard is connected to the PSU, should it be sufficient to shorten the pins for the power switch manually (eg. with a screw driver) to make it start, without actually having connected any of those switches (LED, Reset, PowerUp etc.) ?

Question 2:

Are these kind of mainboards capable of starting without any CPU being installed (I seem to recall, my olden P2B-S would start without one and give me corresponding beep codes)?

GNEP
10th June 2005, 05:32
Q1: Yes - just touch a metal object briefly to connect the power on jumper/connector.

Maggi
10th June 2005, 05:43
Q1: Yes - just touch a metal object briefly to connect the power on jumper/connector.

thought so, tried it already, still no sign of life ... :(

thanx for confirmation though !