Paul wrote:
In article URjEd.32449$3m6.5163@attbi_s51, "Travis King"
wrote:
What's probably the life expectancy of my A7V333 motherboard if I take good
care of it? It has 2 years on it right now. I run the computer for the
most part constantly except when I leave town or do something with the
inside of the computer. Current MB temperature is at 30 C.
If the case temp is not excessive, the electrolytic caps should
be good for 10 years. Solder joints under stress, could be
anyone's guess (more likely to happen with a P4 retail heatsink
and its high clamping forces).
In ten years, you can expect several PSU failures, and any one of
those PSU failures could damage the motherboard.
If you have a lot of lightning storms, or bad quality power,
that could influence how long the mobo lasts. Look carefully
at any modem, cable modem, ADSL wires etc, to see if there are
any protection devices to take a (nearby) lightning hit, before
it gets to the motherboard. For example, on a phone line, there
may be a carbon block at the entry point, and you could enhance
that by using a second protection device nearer the computer.
For the really paranoid, a wireless network would reduce the
wiring exposure to just the power lines. A real ($1K purchase
price) UPS would reduce the risk of an AC power event from
getting you, and would help protect the PSU from getting
damaged. Cheap UPSes offer no protection at all, as they are
actually SPS (standby power supplies) - they are a "straight wire"
to power spikes, and the unit only cuts over to batteries if
the AC power dies for enough milliseconds.
On the motherboard itself, the Vcore circuit is the circuit under
the most stress. If the MOSFETs are cool to the touch, that is
a good sign. I've never read any MTBF estimates for switching
regulators on motherboards, so don't know whether they are
good for a 1 million hour MTBF or not.
Large BGA packages also have a rating, for solder joint
reliability. For example, a BGA with 750 pins, will last for
about 10 years, with a certain daily temperature variation.
From the Via web page:
* 552-pin BGA VT8366A North Bridge
* 376-pin BGA VT8233 South Bridge
so you have little risk of a failure there (caps will fail
first).
Handling the processor a lot (removal, regrease, reposition
heatsink) will cut into the life expectancy, if say the
processor gets cracked, and it happens to overload the Vcore
circuit. If the processor has the rubber bumpers on the top
of the chip, that will cut that risk a bit.
I would say your biggest exposure, is to external factors.
Paul
I would agree, and add that IME motherboards are far more tolerant of
external factors than one has any right to expect ;-)
Our Cottage PC runs an Asus P2B-S, manufactured in 1998 and in service
for almost 6 years. We use it on weekends in winter, but the cottage is
not heated while we are away, so the system experiences repeated thermal
stress cycles - it's common for the inside temperature to be -20C or
lower when we arrive. I discourage the kids from powering up the PC
until the place has warmed up, with limited success :-)
Power is unreliable at the Cottage, and we experience frequent
thunderstorms, however despite a lack of protective measures the only PC
failure which has occurred there to date was a sound card that stopped
working after lightning struck a tree behind the building - no doubt due
to a spike induced in the 40' cable running from the sound card to a
stereo system on the other side of the room. Hardly surprising, but
damage was limited to the sound card.
I expect the Cottage P2B-S to be the first of my numerous P2B series
boards to eventually fail, but perhaps not since I use several in my lab
and subject them to frequent CPU swaps and other hardware changes. My
primary system runs a P2B-DS and has been in service 7x24 since October
1997 except for occasional shutdowns for hardware upgrades or fan
service. The power supply refused to restart after a shutdown in 2002
and was replaced, but no other failures have occurred. I have a total of
11 P2B series boards in regular use, with zero motherboard failures to date.
I'd better start saving my pennies since replacing all my systems when
the electrolytic caps fail in 2008 will be expensive ;-)
P2B
|