No thermal paste on a cpu?

katz

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I'm working on a pc (1997 era) that is used with a John Bean wheel alignment machine in an automotive repair shop. It is booting with some type of DMI error. I didn't see the error, the shop owner wrote it down when he tried to boot it. He just purchased it and is trying to boot it for the first time. An old, well used system by the looks of it.

This computer runs all the software directly from a cd, no hard drive is installed. There are no markings on the pc whatsoever as to what brand, etc. it is.

When cleaning things up inside I removed the heatsink from the Socket 7 cpu and to my surprise there is no thermal paste applied, and doesn't appear that there ever was. In fact, things look very suspiciously clean inside for a 17 yr. old auto shop computer.

Is it possible that the pc ever ran without thermal paste? :confused:

I'm wondering if the person he purchased it from knew of issues with it and tried to clean it up inside before selling it...


Forgot to mention - This is Pentium 166...
 
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We didn't need thermal paste back then. Heatsink and fan was just fine.
My Pentium 200MMX did not have any thermal compound.
Things changed round about the Socket A and Pentium 3-4 days.
 
That is certainly strange and I would expect the CPU to overheat. However, it is conceivable that just the heatsink and no compound could still work.

I looked up the power consumption on the "normal" P166 specs here,
Min/Recommended/Max V core 3.135V / 3.3V / 3.6V
Minimum/Typical/Maximum power dissipation 2.1 Watt / 5.4 Watt / 15.3 Watt
Minimum/Maximum operating temperature 0°C - 70°C

So, as you can see, it would definitely be able to open-air on 3.135v and 3.3v at those wattage's, but I would expect to start reaching 70deg at 3.6v/15.3watt - but, remember, if the CPU is idling it's using little to nil in the way of power even at 3.6v. So, I suppose no grease would provide minimal contact and cooling if that were the case.

Then, and this would be interesting if it is the case, I came across this package "Extended Temperature Pentium®
Processor with MMX™ Technology
" which allows for a case temperature of 115 degrees C! It was produced for smaller form-factor applications and environmental conditions where cooling would be an issue. Sounds like that would fit your client's equipment quite well.

In the early days CPU's were pretty slow (duh!) and their power requirements were pretty low, hence very little heat. If I recall correctly my first Intel 80268 was socketed and no heat sink or fan other than the case fan. In fact, I don't think the 386 or 386dx (387dx) were heat sunk or cooled either. I'm pretty sure that the 486 era started with no heat sink or fan either but later manufacturers started putting on just heat sinks and passive cooling. It wasn't until AMD K5 and 586 chips came out until heat sinks with built on fans became required because of the increased clock speed and higher power requirements.

Just working from memory here. ;)
 
Coincidentally we have booked in a Pentium PC running Windows 98 today!
First thing is to get an image of the drive when it arrives tomorrow. Windows 98 is only booting into safe mode apparently. I shall have to go revisit the good old Win 9x troubleshooting steps.

This is a system that has special software protected by a 'token' on floppy disk...
Not come across this before. I've dealt with hardware dongle but this is new to me.

Sorry for derailing your thread!
 
This John Bean wheel alignment machine does not have a HD installed, everything runs from the CD;

However upon boot I keep getting the DMI pool error stating that no boot disks are found. I've been all through the bios, loaded defaults, etc. - not sure what to do here... Any ideas on how to remedy this? :confused:
 
At that age I would expect capacitor problems etc, what make is the motherboard? And we didn't use thermal paste back then, in fact in the 166Mhz era fans were fairly recent. Some of the more basic 486 SX chips didn't even have a heatsink!.

Can any PC run this software or is there special hardware attached? If the software runs from CD and a floppy I don't see why this old PC still needs to be used. I am thinking a modern PC running VMWare might be able to do the job.
 
Caps are good;

I verified from the manufacture that it will boot from the alignment software. I booted to Linux, no boot - swapped CD with a known good one, tried both IDE channels, no boot. At this point we're calling it a motherboard failure...

We have plenty of new(er) pc's that I could set him up with, but there are four special cards, one using an ISA that I don't have...
 
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I know they make PCI to ISA cards but they're not cheap. A more eloquent solution would be a modern mobo with an ISA slot(s) like this one.

http://www.amazon.com/MB-P4BWA-Industrial-Motherboard-ISA-Slots/dp/B004HLOQH6

Thanks for the link. I'm going through my stash of old motherboards right now to see if I have something that will work. I don't know if he is willing to put that much cash into it at this point, because we're not even sure if the rest of the system is functioning.

In addition to the computer, there is also a "brain" box that all of the alignment pads are wired into - and we can't test that without a working computer that will wire into it.
 
Just wanted to post a follow up on this;

It seems that this pc is very specific designed to work with the alignment machine. There are several connectors present on the motherboard that are not on "regular" motherboards that I've seen. These connect to the brain box and other peripherals.

This is a '97 vintage machine. I contacted the company today about a replacement board/refurb, etc. Wow, was I in for a shock! They do not sell replacement cards/boards separately.

A new replacement computer for this machine is $4500! If we send the old computer back we can purchase the new one for $3000!

Oh, and we pay shipping both ways. This is for a Pentium 166 pc... :eek:

Unbelievable. Also, the stopped creating new software for the machine in 2011, so that is the newest model year that can be serviced with this setup.

Lesson learned here; make sure you do ALL your homework before buying any specific duty equipment.
 
To fair it is very expensive to design none mass produced electronics. With a mainstream motherboard they will sell millions or 100,000s but it sounds like board was designed to work with this machine and they probably only sold in the 100s.

It is not a P166, it is a specialised industrial computer that happens to have a P166 processor in it.

The only other option would be have you tried an external IDE card? The fault could well be with the IDE controller .
 
I do understand all that, especially with specialized equipment, which can be very costly to produce.

This machine probably sold in the "several thousands" at least, maybe a lot higher. Jim Bean alignment systems have been around forever and are very popular in the auto industry.

The only other option would be have you tried an external IDE card? The fault could well be with the IDE controller .

LOL - already tried that one, even attempted to boot an IDE HD with an OS on it and no dice.

It is not a P166, it is a specialised industrial computer that happens to have a P166 processor in it.
Now that's just splitting hairs... :p

All in all, the replacement price still seems a bit outrageous to me. I wonder how many calls they get daily for a replacement pc for this old machine. I guess they would rather it sit on the shelf and collect dust instead of unload it at a reasonable price.

I'm sure they've made their return on this one many times over by now. A mid 2000's modern machine can be had on ebay/other for not a whole lot more money than that. So that's the end of this saga anyway...
 
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