On Tuesday 09 January 2001 10:48 pm, Sridhar Govindarajulu wrote:
> I build a AMD 850mhz system. ABit RAID Motherboard IBM 30 GB deskstar
> HD and 256 Mb memory. It's been working for the past 2 months
> flawlessly. Since yesterday the system reboots or hangs.
> I rebooted the system and had a look at the bios system monitor to
> monitor the temp and fan speed. I noticed when the CPU temp goes
> beyond 109 F the system reboots. I am not sure if this is because of
> a faulty CPU or the motherboard. On the mother board the chipset has
> a separate fan. I suspected the memory and swapped memory form
> another machine, still the same.
Usually it's heat, power supply, or ram errors that cause reboots.
109F = 43C which is well below the 90C max that AMD specs. 'Course a
max of 55C is more practical for problem free operation. The problem
with the temp you see in bios is the system isn't under much, if any
load. A bigger problem with AMD cpu's is there's no provision to
monitor the cpu core temp (ie, internal diode). Readings from a probe
(thermistor) are a guess, no matter how well placed the thermistor is.
Add a minimum of 10C (maybe 15C) to probe temps to approximate the core
temp if the thermistor is in contact with the center of the die and
shielded from air currents (which is pretty much the case with your
Abit).
AMD's need a good heatsink/fan and case ventilation. Tom's, Anand,
and several other hardware sites have done reviews on Athlon/Tbird
HS/F's. Also the heatsink should be firm and square on the cpu die
using thermal grease, not a thermal pad. Case should be ventilated
well enough to keep it's temp at or very close to room temp. Checking
for dust bunnies should be done often and regularly. 2 months might
not be often enough ;)
If it's not a temp problem, try reseating your ram and/or slowing
ram timings in bios. Next thing to check is the power supply. It is an
AMD approved >= 300w, right? FWIW, I read some time ago that AMD
intends to implement a thermal diode in the cpu core like Intel has,
but nothing on it since. Still, the thermistor's better than nothin.
You should use lm_sensors to see what cpu temps are like when runnin
prime95 (torture test), or better yet, cpuburn. This is when you don't
want to see anything over 55C, and cooler is better.
A good source of info for your system would be
alt.comp.hardware.overclocking.amd (even if you'd never consider
oc'ing) and alt.comp.periphs.mainboard.abit newsgroups.
--
Tom Brinkman [EMAIL PROTECTED] Galveston Bay
