psrc@pegasus.ATT.COM (Paul S. R. Chisholm) (01/23/90)
In article <75971@tut.cis.ohio-state.edu>, tim@VAX1.CC.UAKRON.EDU (Timothy H Smith) writes: > I've had the machine about 20 some days and already have had 2 > motherboards replaced. I'm no hardware guru, but that sounds like a bad power supply to me. If it is, you're likely to see more inexplicable hardware failures as time goes on. Does anyone know if there's any way to test a power supply (other than hooking it up to an expensive mother board and seeing if it blows?-) > Timothy Smith, tim@vonneuman.math.uakron.edu Paul S. R. Chisholm, AT&T Bell Laboratories att!pegasus!psrc, psrc@pegasus.att.com, AT&T Mail !psrchisholm I'm not speaking for the company, I'm just speaking my mind.
wg@cbnewsm.ATT.COM (Bill Gieske) (01/25/90)
In article <4417@pegasus.ATT.COM>, psrc@pegasus.ATT.COM (Paul S. R. Chisholm) writes: > Does anyone know if there's any way to test a power supply (other than > hooking it up to an expensive mother board and seeing if it blows?-) My power supply went last month, and how I was told to verify it was bad before shipping it back was to measure the voltages - +5, -5, +12, -12. If I recall correctly the +/- 5 volts must be within 10%, or no less than 4.6V, and the =/- 12 volts must be within 10%, or no less than 11V. The power supply may have a note on the case indicating which wires contain which volts. If not, you'll have to punt. There is also a wire coming from the power supply that indicates there is sufficient power coming in so that the system should con- sider itself as capable of running - called power good (AT only?). If this is too low, the system will not attempt to come up. This is supposed to pre- vent the system from thrashing if the power level fluctuates. Try testing the power supply with no load, with only the motherboard hooked up, and then with the hard disk and possibly the monitor card. Voltage levels should stay within tolerance. The good news here is that although the system potentially thrashed about as the power supply died, nothing on the hard disk was corrupted, nor were any cards damaged. I sent both the power supply and motherboard back and got replacements for both, but was not clear as to whether the motherboard was really damaged. Good luck. Bill Gieske cbnewsm!wg
RR.PPE@forsythe.stanford.edu (01/25/90)
In article <4417@pegasus.ATT.COM>, psrc@pegasus.ATT.COM (Paul S. R. Chisholm) writes: >In article <75971@tut.cis.ohio-state.edu>, tim@VAX1.CC.UAKRON.EDU >(Timothy H Smith) writes: > >> I've had the machine about 20 some days and already have had 2 >> motherboards replaced. > >I'm no hardware guru, but that sounds like a bad power supply to me. Funny you should say that....... We have a Dell 286 which killed two hard drives (replaced under warranty) and eventually a third along with the power supply (no longer under warranty). That's when we found out that the computer came with an *85 watt* supply for a machine that size. We bought a reasonable 120 watt supply and have had no more problems. Dell, by the way, never replied to our correspondence on this problem.
young@turing.seas.ucla.edu (Brian B. Young) (02/28/90)
Help!! Could someone please direct me to a supplier of externally mounted
cooling fans for IBM PC type machines? I believe there was once a fan called
"Turbo Cool," but I have been unable to locate one locally. Thanks.
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