VOGONS


First post, by pixecs

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I aquired, what appear to be, a PCPartner MVP3BS7-954 motherboard with a lot of damaged or missing components.

Here is a list of missing ones:
Transistors: Q1, Q3, Q5
Capacitors: C66, C67, C69, C207, C224, C225
Inductors: L8, L9, L24
Resistors: R4, R8, R17, R23, R197, R198, R203
Resistor network: RN5

I suppose electrolytic capacitors should be around 1000uF, but the MLCCs are unknown value
I could recreate inductors because i have other faulty boards and ferrite cores.
Resistors are unknown
Resistor network is probably a 4.7K
Transistors are unknown
U25 & u26 and adjacent components appear to never been populated.
I do have a spare socket7 socket.

Could someone give some hints for this missing components?
Thanks

Reply 1 of 5, by pixecs

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I tried to fix it but I failed miserably.
What i put:
Q1 - PNP transistor
Q3, Q5 -NPN transistors
R4, R5, R17, R23, R197, R198, R203 - 22 ohm resistors
RN5 - 4k7 resistor network
C66, C67, C69 - 100nF MLLCs
C193 - 10uF/10v
C176, C179, C180, C181, C182 - 1200uF/6.3v
C223, C224, C225 - 1000uF/6.3v
C118, C333 - 100uF/10v
L8, L9, L24 - inductors with the appoximative size and number of spires as in theretroweb page
added a Socket7 socket

The CPU power voltages are spot on.
The CPU resets ok but BIOS is never read.
CPU measurements on power on:
EADS# - high
ADS# - high
HOLD - low
BOFF# - high
AHOLD - 1 high pulse
FLUSH# - high
BUSCHK# - high
IGNNE# - high
STPCLK# - low
INIT - high
KEN# - high

Reply 2 of 5, by Dorunkāku

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Did you also fix the cache chip in the socket footprint? It seems to have been knocked to the right.

Reply 3 of 5, by pixecs

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Yes, I desoldered the chip and fixed 3 pads which where lifted from board and also i straigneded skewed pins.
Soldered back the cache chip with 1 remaining pin unconnected because the pad was missing... the pin is number 127 wich on docs in marked as NC.

Reply 4 of 5, by pixecs

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Also changed the 32k7 clock oscillator as it was non functioning.

Reply 5 of 5, by pixecs

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here is the board