P5B-VM G965 mobos overheating

I've got 2) Asus P5B-VM that seem to overheat big time (motherboard;
processor runs cool). Anyone else have any problems with these
boards? Any solutions? Running:

E6400 core2 duo
1 gig ram (Corsair DDRII-800)
Well ventilated mAtx case (overheats the same with case open or
closed), with 2 fans (in addition to the PS fan)
250 gig hdd
Latest bios as of a few days ago.

Temps start out cold in the low 20's celsius for both the cpu & the
motherboard. After a few minutes the motherboard temps start to creep
up. After about 15 minutes, the one board is over 45 degrees celsius
and throwing alarms in Asus Probe II. The other is a few degrees
cooler in the low 40's. Both CPU's stay in the low 30's. All this is
at idle, with minimal power management and all the Intel chipset
drivers installed.

I've heard the 965's run hot, but this is ridiculous. Any ideas?

RichH wrote:
I've got 2) Asus P5B-VM that seem to overheat big time (motherboard;
processor runs cool). Anyone else have any problems with these
boards? Any solutions? Running:

E6400 core2 duo
1 gig ram (Corsair DDRII-800)
Well ventilated mAtx case (overheats the same with case open or
closed), with 2 fans (in addition to the PS fan)
250 gig hdd
Latest bios as of a few days ago.

Temps start out cold in the low 20's celsius for both the cpu & the
motherboard. After a few minutes the motherboard temps start to creep
up. After about 15 minutes, the one board is over 45 degrees celsius
and throwing alarms in Asus Probe II. The other is a few degrees
cooler in the low 40's. Both CPU's stay in the low 30's. All this is
at idle, with minimal power management and all the Intel chipset
drivers installed.

I've heard the 965's run hot, but this is ridiculous. Any ideas?



If it bothers you, you can add an 80mm fan to your computer
case. What I do, is buy a piece of aluminum angle iron (L-shaped
cross section). Drill a hole in one end, such that the piece of
angle iron can be bolted to the same place as a PCI slot
cover. The fan then affixes via tie wraps, to the angle iron.
I use a setup like that, to allow an 80mm fan to blow on my
"fanless" video card.

To keep things in perspective, remember that 37C is human body
temperature. 45C is not much hotter than that. So it isn't
burning up. With sensors on motherboards, you don't know where
the sensor is located, and whether it is registering properly.
Touching the heatsink, might give you an idea of whether any
parts in the computer are running hot. And placing a fan
where necessary, can help couple the heat, into the general
air flow.

To complete your temperature characterization of the system, you
should attempt to run a 3D game, using the built in graphics. It
could be that things will get hotter than they currently are.
Running a 3D game will highlight whether additional cooling
is required. (Since the Vista operating system will leave
3D graphics enabled, for the Aero interface, that is an
example of an OS that may leave the chipset in a hot state
at all times.)

It can take surprisingly little additional cooling, to achieve
an improvement. I modified the cooling in a prebuilt computer.
In that one, the 865G Northbridge temperature, was rising above
75C (as measured by a separate digital thermometer I taped
to the heatsink). I fitted a 40mm fan, which only produces
a small flow in cubic feet per minute (CFM). That fan was
able to bring the temp down to 37C or so. The major chips
on your motherboard do have heatsinks, so a little bit more
fan induced airflow should fix you up.

If Asus had fitted a fan, it would only be a low quality
one. Now you have the luxury of finding a quality fan
(ball bearing or ceramic bearing), that will last for
years.

Paul

see bottom post

"Paul" wrote in message
...
RichH wrote:
I've got 2) Asus P5B-VM that seem to overheat big time (motherboard;
processor runs cool). Anyone else have any problems with these
boards? Any solutions? Running:

E6400 core2 duo
1 gig ram (Corsair DDRII-800)
Well ventilated mAtx case (overheats the same with case open or
closed), with 2 fans (in addition to the PS fan)
250 gig hdd
Latest bios as of a few days ago.

Temps start out cold in the low 20's celsius for both the cpu & the
motherboard. After a few minutes the motherboard temps start to
creep
up. After about 15 minutes, the one board is over 45 degrees
celsius
and throwing alarms in Asus Probe II. The other is a few degrees
cooler in the low 40's. Both CPU's stay in the low 30's. All this
is
at idle, with minimal power management and all the Intel chipset
drivers installed.

I've heard the 965's run hot, but this is ridiculous. Any ideas?



If it bothers you, you can add an 80mm fan to your computer
case. What I do, is buy a piece of aluminum angle iron (L-shaped
cross section). Drill a hole in one end, such that the piece of
angle iron can be bolted to the same place as a PCI slot
cover. The fan then affixes via tie wraps, to the angle iron.
I use a setup like that, to allow an 80mm fan to blow on my
"fanless" video card.

To keep things in perspective, remember that 37C is human body
temperature. 45C is not much hotter than that. So it isn't
burning up. With sensors on motherboards, you don't know where
the sensor is located, and whether it is registering properly.
Touching the heatsink, might give you an idea of whether any
parts in the computer are running hot. And placing a fan
where necessary, can help couple the heat, into the general
air flow.

To complete your temperature characterization of the system, you
should attempt to run a 3D game, using the built in graphics. It
could be that things will get hotter than they currently are.
Running a 3D game will highlight whether additional cooling
is required. (Since the Vista operating system will leave
3D graphics enabled, for the Aero interface, that is an
example of an OS that may leave the chipset in a hot state
at all times.)

It can take surprisingly little additional cooling, to achieve
an improvement. I modified the cooling in a prebuilt computer.
In that one, the 865G Northbridge temperature, was rising above
75C (as measured by a separate digital thermometer I taped
to the heatsink). I fitted a 40mm fan, which only produces
a small flow in cubic feet per minute (CFM). That fan was
able to bring the temp down to 37C or so. The major chips
on your motherboard do have heatsinks, so a little bit more
fan induced airflow should fix you up.

If Asus had fitted a fan, it would only be a low quality
one. Now you have the luxury of finding a quality fan
(ball bearing or ceramic bearing), that will last for
years.

Paul

Thanks Paul for the suggestions. I used Prime95 for my torture
testing; it seemed to provide enough stress to heat the chips up. I
found one of the mobo's had defective heat sink compound on the
northbridge chip. I replaced it, and now it runs as cool (or hot!) as
the other (was 5 degrees different). I still don't like
northbridge/mobo temps in the 45-55 degree celsius range (especially
at idle), but they seem stable. As for meltdown temps, as I'm sure
you know the upper limit of operation for most silicon chips is 70
degrees celsius. In my experience, most systems start having failure
problems well before that temp. BTW as noted above I have a well
ventilated case with 3 fans. The system does not run any cooler with
the case open, and as for northbridge fans -- I'm through with those
due to too many problems in the past like noise, failure, etc. Only
passive cooling for me , or I'll use another product.

I still have problems with the fan controls on these boards -- on one
the cpu fan runs around 1700 rpm, the other around 600 with fan mgmt
turned on in the bios. Temps do not seem to matter. When I turn fan
management completely off, they both run at 1700. These are in
identical cases with identical fans, etc. I finally just set the one
running @ 600 rpm to a higher bios setting and now it runs about 1200
rpm, but this just seems hoky. these mobos do not seem to be normal
Asus quality. I wish the major reviewers would start paying more
attention to fan controls -- the percentage of mobos where the fans
controls work properly is pretty dismal.

Rich