Help me solve this mystery.

M76

M76

[H]F Junkie
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I wonder if anyone has an idea on this: I've opened up an old PC (P4) and found a strange device attached to one of the molex power connectors. It's basically a small black box 1 by 2" maybe. That was completely sealed.

After peeling off the enclosure (it was glued shut really tight) I've found that the insides are enclosed in some sort of plastic. It's like they poured the plastic into it as liquid and it set around the components fully enveloping them including the entire PCB. It is solid now, there is no way to get to the pcb to see the traces or components on it without causing major damage.

The only components that are not fully enclosed in the plastic mold, are two Thrystors. (BT151 and BT152).

What the hell could this be, and what is it's function?

It has no outputs, no other connections of any kind, it's only external connection is the molex power connector.


Since it is so secretive of it's insides my first thought was: CIA listening device :-D

My second thought was that it's some sort of overvoltage protection.
I'm no expert at electronics but I assume that would have to be connected in line with the components to function. Not parallel to them, right?
 
FlamingTP01 said:
picture?
Click to expand...
Sorry, I don't have a picture but it's not hard to picture a black box, with a male molex power connector.

Here, I've created a mockup.

Black-Plastic-Electronic-Box-Instrument-Case2.jpg
 
M76 said:
Sorry, I don't have a picture but it's not hard to picture a black box, with a male molex power connector.

Here, I've created a mockup.

View attachment 111250
Click to expand...
Only purpose I could think of is a transmitter.

dthree said:
Do you have a supermicro motherboard?
Lol read this article: https://www.bloomberg.com/news/feat...ny-chip-to-infiltrate-america-s-top-companies
Click to expand...

Last I checked apple and amazon have both denied this. not that I would be surprised if they were lying. Hard to play ball when you could lose access to the Chinese market.
 
from what I looked up, molex doesn't send or receive data. Gotta be wifi, GPS, or bluetooth, maybe a mic? Take it to a spy store if you have one in your area (yes those are real) and ask. Maybe send an email to some of those ex secret service people who privately contract in finding bugs and such. All I can think of.
 
First thing that came to mind was something of a lowjacking device, but I wouldn't hedge my bets on it. That is certainly interesting... I wonder if there is a way to kill the blue (epoxy?) and expose the circuitry further.

Maybe turn it over to the masses of Reddit, a wider audience might make short work of it.
 
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Probably for a cold cathode light is my guess.
 
Is there also a coin battery present on the mobo for the CMOS/RTC?

Some older systems used to have an external battery pack that plugged into the mobo.
They usually plugged into a special connector though, not a molex like that.

Plug it into a molex and let it run for a while. Then pull it off and see if you find voltage on it.

ETA: I've also heard of fixes (never seen one) for cold boot problems. Older systems used to often have a problem with cold boots.
System would not POST if left off for a while, but would then POST and run ok after re-powering. The mobo
was looking for POWER_GOOD before the PSU was ready. It could be a battery pack to help fix cold boot
problems, dunno.

.
 
Last edited:
Esso said:
First thing that came to mind was something of a lowjacking device, but I wouldn't hedge my bets on it. That is certainly interesting... I wonder if there is a way to kill the blue (epoxy?) and expose the circuitry further.

Maybe turn it over to the masses of Reddit, a wider audience might make short work of it.
Click to expand...
I don't have reddit, not familiar with it at all. If you're up for it you can post it there with the picture and the description I gave.

elite.mafia said:
Probably for a cold cathode light is my guess.
Click to expand...
In a beige stock computer case from one of our countryside offices? NAH.

Spartacus said:
Is there also a coin battery present on the mobo for the CMOS/RTC?

Some older systems used to have an external battery pack that plugged into the mobo.
They usually plugged into a special connector though, not a molex like that.

Plug it into a molex and let it run for a while. Then pull it off and see if you find voltage on it.

ETA: I've also heard of fixes (never seen one) for cold boot problems. Older systems used to often have a problem with cold boots.
System would not POST if left off for a while, but would then POST and run ok after re-powering. The mobo
was looking for POWER_GOOD before the PSU was ready. It could be a battery pack to help fix cold boot
problems, dunno.

.
Click to expand...
It's not that old system it's a PIV it has a cmos battery. And there is definitely no battery in this thing. Look at the picture, there is no space left for a battery there. I still think the most likely and benign explanation that it is some sort of surge protection. This is from the era when all kinds of shitty psus were sold on the cheap, with exploding capacitors that often fried computers.
 
M76 said:
I don't have reddit, not familiar with it at all. If you're up for it you can post it there with the picture and the description I gave.
Click to expand...

Sounds good, I'll create a thread.
 
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My guess is that it's it's a DC-DC converter to supply extra current from one voltage rail to another. P4 came around during the time that motherboards were moving from supplying CPUs from 5v to 12v. So maybe the system builder used a older PSU that supplied more 5v current, but the motherboard needed more 12v?
 
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