"Paul" wrote in message ...
JFG wrote:
"Paul" wrote in message
...
JFG wrote:
Hey, all,
I'm back with a problem that I hope is curable, but I fear the worst.
I was given a Satellite A45-S250 by a family member. It intermittently
booted up but didn't run for long. It had the problem of BSD after
memory dump on a regular basis. I looked up the error message and many
suggested bad RAM. I replaced the RAM with known good RAM and the
problem persisted. I disabled all the peripherals I could and tried to
load a fresh install of XP. This didn't work. Long story, short: I
thought I might have a burnt CPU so I took out the P4-2.8 Celeron that
runs at 533 and replaced with a P4 M 1.6 that runs at 400. According
to the Toshiba website the mobo should run either. I tried booting the
laptop with the 1.6 and it wouldn't boot. So I replaced the 1.6 with
the original 2.8 and now the laptop won't boot at all with the 2.8. It
does not go into the BIOS even though the lights come on and I hear
activity in the cd-rom. I fear that I might have blown the motherboard.
Anyway, if anyone has suggestions as to what I might do at this point
beyond getting a new mobo I'd like to hear them. Again, thanks to any
and all who take the time to suggest possibilities. JG
Examine the socket and the processor carefully, for connection problems.
If there is a lever, or a screw that clamps the ZIF socket into place,
make sure it is secure. Make sure the physical assembly was all put back
the same way (thermal paste, heatpipe heatsink onto processor, and so
on).
The Celeron would not burn, because it would have THERMTRIP. If the
heatsink falls off, the THERMTRIP signal is available to kill power
to the processor. So in theory, you shouldn't be able to burn a
processor. Both modern Intel and AMD processors now have THERMTRIP.
You'd have to go back to some of the early Athlons, to find cases
where the protection is less than ideal. (My AthlonXP motherboard,
has a separate eight pin chip, which monitors the temperature and
does the equivalent of THERMTRIP.)
You can check for THERMTRIP, by downloading the datasheet for the
processor. One way to do that, is go through the list of Celerons
here, select an appropriate one, and then see of there is a
documentation
link.
http://processorfinder.intel.com/
I wouldn't panic yet, because I interpret your results to suggest
something isn't assembled right. Like turning the screw on one of
those small ZIF sockets, to lock it.
Paul
Great post, Paul. Very good information. The cpu socket is one of those
with a lever. I checked the cpu itself for bent pins, etc and it appears
ok. It is locked tight in place and I'm pretty sure I put the cooler
assembly back correctly. You've convinced me that I haven't burnt the
cpu and now I'm wondering if I didn't do some harm to the motherboard.
The laptop wasn't working properly when I started on this project and now
it doesn't go to BIOS. I haven't completely given up on the one I have
yet. I'll try reassembling it today. I'm thinking that what I'll end up
doing is buying an equivalent unit from ebay with a broken screen and
missing parts. I'll cannabalize the one I have and make one good one.
Thanks for your response. JG
To know exactly what you did, I'd want the SLxxx number off both
processors. One of the differences on a mobile processor, is
there are a couple signals for SpeedStep. But that shouldn't harm
it. For example, people buy SL726 processors, and install them
in desktop boards, to overclock them. You can raise an SL726 to
FSB1200, causing the core to run at 3.6GHz, and I'm told they
run pretty cool while doing so. So I don't necessarily see the
installation of a mobile processor, as a death sentence. But
to know more, you'd want to use the code on the processor,
and look it up, to see exactly what it is. From that generation,
I don't know if there are any ULV (ultra low voltage) versions
of S478 chips or not. But it is easiest to trace this info,
by using the SLxxx number.
This is the mobile that overclocks so nice. It runs at a lower
speed than the stated values on this page, when plugged into
a desktop board, which is why it ends up at FSB1200 and 3.6GHz core.
The reason I'm interested in that one, is it would fit perfectly in my
current motherboard (P4C800-E Deluxe), which can apparently
overclock that high. I've run into a few people who buy these,
and don't know what a good deal they got (they're puzzled by
the speed it runs at).
http://processorfinder.intel.com/Det...px?sSpec=sl726
Paul
Turns out that you were 100% correct. I had not put the original CPU back
in correctly. It was slightly cocked and rocked a little before putting
down the lever. After installing correctly, the laptop then booted. So, no
harm no foul on the CPU switch. However, the original problem remains -
that is, the occasional BSD with the quick message of memory dump. I have a
couple of new sticks of RAM coming in and I'll see if that makes a
difference. Meanwhile I've bid on an equivalent model on eBay that has no
peripherals and a broken screen. If the motherboard on that one works, I'll
be in high cotton if I win it and can cannabalize my unit successfully. I
have to wait one week for that since the auction doesn't end until then. In
the nonce, I'll continue to fool around with the one I have here.
I appreciate your taking the time to find out all the helpful information.
Best, JG