Can this IBM adapter be used for Compaq?

I just bought a 2nd-hand Compaq laptop.
It's an older one with 1.3ghz (I wanted a low power one)

Anyway..
It came with a non-Compaq cheapo adapter, which becomes burning hot to touch after just a few minutes plugged in, and that scares me.

The specs of the cheapo burning-hot adapter are:
INPUT 100-240v~ 1.6A(1.6A)50-60 Hz
OUTPUT 18.5V 3.5A LPS

The specs of my NON-burning IBM (X31 thinkpad) adapter are:
INPUT 100-240v~ 1.5a-0.9a 50/60Hz
OUTPUT 16V 4.5A

Can the adapter with the blue-colored specs be used in place of the adapter with the red-colored specs?

 

The power tips are likely to be different, so unless you're willing to perform some surgery on the IBM adaptor (changing out the plug), it's unlikely to work as a straight plug-in. As well, the voltage difference is a bit more than I'd feel comfortable with, personally.

 

By power tips, I suppose you mean "prongs".

The cheapo adapter has 3 prongs, and the IBM has 2 prongs.
Both would be pluggable into my TrippLite surge-strip.

By "voltage difference" I guess you mean the 18V vs. 16V?
What does "output" mean, in this instance?
Doesn't it mean, what the adapter puts back into the wall wiring, after circuiting thru the CPU? and if so, isn't it actually safer to spit back out 16V rather than 18V?

My main question, is:
If an AC adapter gets burning hot, doesn't that mean that something (either the adapter or other components) will wear out quicker, or be a fire hazard? Or even cause a higher electric bill, or EMF emissions?

Can someone please give me a clue?
Or else tell me which key words to key into google to find the answer?

 

No, he means tips
...meaning what you plug into the laptop.

Regardless, NO, it will not work. Thats a bad idea. The first is not "a hot adapter" it is simply not powerful enough for the computer.

3.5 x 18.5 = 65w
4.5 x 16 = 72w

Its likely that you need 90w. The laptop will probably say on the bottom.

 

OK, I checked the underpart of the Compaq, and it states:
18.5V 3.5A

So apparently, the adapter I was sent (even if not the original) has the right specs printed on it.

But yet it gets burning hot. So what to do? Is it safe? Will anything wear out quicker?

BTW, I forgot to mention that I tried the IBM's tip in the Compaq's socket, and it actually fits in more precisely (i.e. less loosely) than the cheapo one

 

As niffcreature said, by power tips I meant the plug that you actually plug into your notebook. And yes, by voltage difference I meant the 18 volts vs the 16 volts. The input the power adaptor refers to is what goes into the adaptor from the wall, basically the plug that goes into the wall socket. The output is what the adaptor puts through the other wire that plugs into your notebook. I am not as convinced as niffcreature is that the supplied adaptor isn't powerful enough for the notebook, but without a model number, there's no way for us to check. An adaptor that gets burning hot can be a hazard, yes, depending on exactly how hot it is getting. The problem is that we don't really have enough information to tell what the problem is for sure. For example, the "cheapo" adaptor may simply not be up to spec, as in, even though it states that it's designed to take in 100-240v ~ 1.6A and output 18.5V ~ 3.5A, it's not efficient enough to do it properly, and thus it actually is drawing more power than listed to output enough power. Your best bet is to lookup the Compaq model, and see what rating adaptor was originally supplied with the model.

Edit - even if the tip fits, prolonged operation with a mismatched power adaptor can burn out or otherwise damage the internal power circuitry of your notebook. A higher rated power supply (wattage) is fine, as a notebook will only draw as much power as it needs, but mismatched voltage can be a problem. And just because a tip fits, does not necessarily mean it will work. Some tips have been known to reverse the polarity (instead of negative inside, positive outside, they're positive inside, negative outside, for example), and others, even though they may appear to fit, will not make full contact and will not provide power.

 

Point in case, even though it may fit you may possibly FUBAR your motherboard and it isn't worth it. Go buy yourself an OEM adapter.

 

Judicator, thanks for the lengthy explanation (though I can't say I'm not still confused except to think of it as, for example, making sure to have enough water in your canteen, even though you may not need to draw on all of it.

I'd actually thought electronics worked the opposite.
i.e. I had thought that if you input more voltage such as 18V into the CPU, it would fry it more than if you'd put in 16V.

Now, re: the Compaq:
It's the N620C 1.3ghz

Re: the "no-name" adapter:
Maybe this will help:
It states HK-C-015
Also:
"Replace with Part No. PPP009L PA-1650-02C
FCC Tested To Comply With FCC Standards
For Home Or Office Use

 

Hm. Ok, so it's a Compaq Evo, and it's listed as taking a 65 watt adaptor, at 18.5V ~ 3.5A, so the unbranded adaptor at least seems to fit the appropriate specs. It may just be at the low end of them, which is why it runs hot. It may be worth getting a 90 watt 18.5V adaptor, if you want a cooler running adaptor.

As for the voltage mismatch, it's a bit of both. With a lower voltage than the power regulation circuits expect, they may end up drawing more current (amperage) to compensate, which would end up burning out supply wires. Remember that the point of power regulation is to convert the power that flows into the notebook into the various voltages and amperages needed to power each of the individual components in the notebook. As for what I was saying about drawing as much power as it needs, while a 90 watt adaptor for your N620C might be rated at, say, 18.5V ~ 4.8A, what this really means is that it supplies up to 4.8A of current at 18.5V. This means that your N620C would draw 3.5A of the 4.8A possible, at 18.5V. This is what I meant by a notebook drawing only as much power as it needs; current draw is fairly easily adjustable, but changing voltage can get tricky, which is why I emphasized that the voltage difference is what troubles me. Usually, a voltage difference of maybe 10% is tolerable (although not recommended), but going from 18.5V to 16V is a bit further than 10%, which is why it makes me uncomfortable.

Remember that it's not just voltage, it's amperage as well. The amount of power that actually passes through is voltage * amperage = watts. Those famous Van de Graaff generators (the ones that make your hair stand on end if you touch them) operate at extremely high voltages, but remain safe because they put out very low amperage (current). So if you put 18V through a CPU with very, very, low current, it might not fry it, but putting through 16V at a higher current could fry it. Voltage is only one part of the equation.

 

OK, thanks for the further explanation, though guess what - the laptop had come with a Linksys WIFI card stuck into its left side (with an associated hi-pitched whistling noise). Now that I removed it, the adapter isn't as burning hot - merely warm (though I hope won't get any warmer!

(btw, I use Ethernet, preferring to avoid wireless due to EMFs

But I still hear this whistling sound.
But when I tried to get to Control Panel (like most normal Windows systems ought to have), all I saw upon START, was:
Programs>
Documents>
Settings>
Search>
Help
Run

I did not see Control Panel, nor My-Computer.
So I clicked Settings>
& therein saw Control Panel

But when clicked Network connections, all I saw was LAN.
I couldn't figure out where to find if WIFI is enabled.

Cuz what else would cause this background whistling?
I'm not saying the whistling is loud - more like "elusive"
But it drives me nuts, since its waves don't resonate with my tolerance.

I still don't know where the heck My-Computer is supposed to be in this tweaked system. I can't believe my crazy luck. To be on the safe side, I'd bought two, rather than just one, refurb laptops this month and BOTH had been tweaked by previous users to the Nth degree. Like - lightening struck twice. It's matrix-like, similar to my often glimpsing the time as either 2:22am or 5:55pm or 11:11. Similar to my register receipt being $6.66 on June 6, 2006. yes really - me inside the matrix. So now, besides a zillion other pressures I can't deal with including blizzards, a crown falling out & possible root canal, geriatric parents, I'm busy racing the clock trying to juggle what to do with these laptops. I decided to go ahead and buy Square Trade for the Thinkpad I'd bought (the Thinkpad has issues with a too-noisy fan sometimes causing data-entry to be delayed, that's aside from its tweaked system), but should I get the warranty also for the Compaq? Decisions, decisions.

 

Okay, a little bit of mis-information in this thread (although the intentions seem good).

The too hot power supply is simply because it is simply built as cheap as possible. I too recommend getting an OEM power adaptor, but note that it too may run warm with your notebook - but at least the manufacturer will know this and have taken it into account when spec'ing and deciding on the parameters of the internal circuits and materials.

As far as the voltage goes, a lower or higher spec'd voltage by itself (18.5 vs. 16) is not better or worse: it is simply what the circuit needs and calls for. What is important is to match the supplied Voltage and ensure that the Amperage is at least able to match (doesn't matter if it can deliver more Amps) the spec's of the notebook.

When you use a 16V power supply with a circuit (your notebook) that is spec'd at 18.5V (a 16% difference, btw) the notebook will be running in 'brown out' conditions - continuously. This can seriously effect the stability and longetivity of the system just as much as giving it significantly higher voltages would (over 10%).

What it won't do is draw more amps though (with a lower voltage): that is dependant on the resistance of the circuit as a whole and this resistance does not change depending on what Voltage is applied.

When the correct voltage is applied the current is as expected.

When more voltage is applied, the current (Amperage) increases because the resistance does not change (can't change).

When less voltage is applied, the current decreases because the resistance is a constant for any specific circuit. This is also why it would be operating in a 'brown out' state: the lower amperage caused by the lower voltage will be making the components work at their worst case scenarios (and not just for a few seconds or minutes as a real life 'brown out' would - but continuously (that is the dangerous part for your electronics at a wrong/lower voltage).


Judy Smith, if you can get a quality power adaptor with the proper 'plugs/tips' to fit the notebook, with the correct output Voltage (even if the Amperage is higher - don't worry, the notebook will only take what it needs - as long as the Voltage is 18.5V as spec'd for your notebook) then you should be fine.

As a matter of fact, if you do get a 90W (watts) adaptor instead of 65W as spec'd for your system, it will run significantly cooler (and should last longer too), but it will also be physically bigger, don't forget!

There are 5 things to pay attention to:

1) Buy a quality (OEM) product - a few dollars more here is worth the cost to keep your system, your power supply or even your office/house from frying.

2) Match the Output Voltage exactly! This one is not up for discussion.

3) Make sure the 'plug/tip' is the exact one specificed for your notebook. Also, the size, polarity and any other special fit/construction needs to be 'exact' not 'close' or 'good enough' too.

4) The output current specification, as long as it equals or surpasses the notebooks spec's, is really not important. But, assuming the output voltage is constant (eg. 18.5V), then a higher current spec will usually mean a physically bigger power adaptor.

5) The Wattage of the power supply (eg. 65W vs. 90W) is non-critical too (electrically) as long as the Output Voltage is on Spec. What will affect the wattage of the power supply is how many amperes the power supply can sustain at the specificed voltage (multiply these two values together to get Power in Watts).


P=IxE

Where Power (in Watts) equals current (in Amperes = I) multiplied by voltage (Volts = E).


Hope this clears things up for you a little?

Good luck.

 

Whistling or high pitched noises are created by inductor coils.

Unfortunately its considered to be somewhat normal. I don't think that square trade or any other warranty will help you with this unless its pretty loud.
Your best bet with that is probably to get a system of the best build you can find, like IBM/Lenovo, hopefully you wont have the issue with your other laptop.

There is also a way to repair it by finding the actual inductor on the motherboard and using a type of insulating glue but that would of course involve taking apart the entire thing.
...I can't imagine what it would be like to be so consciously sensitive to EMFs. i guess personally I have long since given up and assumed that they were controlling my mind in an irreversible intangible way.

regards

 

Could the "whistling" be the fan? Without actually hearing it, it's a little difficult for us to say. The hard drive spinning could also be a possible culprit, although I don't know that most people would describe that as "whistling". Someone else on google has mentioned an "AC power whine", but there doesn't seem to be enough comments on it to be able to tell if it's endemic to the entire model line.

The Compaq N620c Evo does not seem to have come with a built-in slot for a wireless card, by the way, which would be why it had the attached Linksys WiFI card; this also explains why you can't find a WiFi connection.

As for the My Computer thing... I wonder if you should just wipe the whole thing and install from scratch. It might solve some of your headaches with finding things. Otherwise, if you let us know your OS, we can see what else we can do to help.

I would agree with you if the power regulation was a fixed resistance circuit; the thing is, it's not. After all, your notebook will draw different amounts of power depending on how much "work" it's doing, and since the voltage is fixed, that means it's going to be drawing different amounts of current to get the different amounts of power. This means that it automatically will vary the resistance to get the power that it "wants". Now, the question of course, is whether it does this according to a specific table (such as X resistance for Y demanded power draw), or if it just "adjusts" the resistance dynamically until the components "tell it" that they're getting enough. If it's the former, then current load will probably not go over, but if it's the latter (or if the former table is based on wattage; i.e. it's checking the wattage coming through with means it needs to draw more current to get the right wattage for the P=I*E law you mentioned) then we have to worry about "overdrawing", as I put it. It would probably depend on how the ODM designed it at that point, and I'm not sure they'd want to bother telling us.

We still agree on the basic points, though. Oh, and for the record, here are some posts about insufficient power supplies burning out motherboards. The post is specifically about power supplies with insufficient wattage or amperage, but incorrect voltages can have the same effect.

 

Judicator,

I was trying to make it simple for Judy...

The resistance is 'fixed' in the sense that without modifying the circuit, the resistance cannot change by itself (and that, along with the Voltage applied) is what determines the current that is drawn (and not that the current available is able to be 'forced' into the circuit).

The 'gotcha', of course is that the circuit can be modified - as you stated.

However, keep in mind that the power requirements of the computer as written on the bottom panel (18.5V @ 3.5A) is the maximum that the system can use as long as it is operating within specs. As long as we meet the minimum amperage that the system calls for, we are safe (assuming the correct Voltage too, of course).

Now, while the circuit can be modified, it is not at all how you assume.

The circuit (as a whole) is modified by turning on/off different devices, or by modulating their maximum states. This in turn presents a different load (resistance) to the power supply and therefore use different amounts of power depending on what we were doing with the notebook at that time...

But there is no way it can 'adjust' the circuit's resistance (nor can a circuit 'ask' for more power') as you suggest.

All it can do is turn on/off different circuits so that the total load presented to the power supply changes.

If your suggestion of changing the resistance of a given circuit dynamically worked, we could lower it (along with using lower input voltages) to decrease the heat output, increase battery life and use smaller power adapters too.

 

niffcreature, thanks, though I don't have the kind of experience necessary for taking apart laptops. Nor the time or inclination at this point.

tiller, the adapter issue has been resolved (see above.

Judicator, Re: the Control-Panel, the seller instructed me how to switch from classic view (which is what he used) and that put it back to the normal default start menu.

Re: the whistling, the seller has responded to me that he doesn't know what i'm talking about; that he never heard whistling in 6 years of owning this laptop.

But I'm still hearing this whistling & it's driving me NUTS!
It's sorta like hearing a cricket outside a house in summertime, albeit with windows closed, such that it's very faint. But horrible!

It's definitely not any fans - I know what laptop fans sounds like, and this is not a fan. It's the same pitch whistling as when the WIFI was stuck inside, albeit much fainter.

Why do inventors create such tools of torture which exacerbate or bring on electrosensitivity? They should be made to go thru the illnesses they impose on others. And why impose artificial tinnitus on myself, when I have enough other stuff to deal with...

The worst of it is, that I was all excited at getting such a low, 1.3ghz laptop with sufficient specs, only to find that it has high pitch frequencies of whistling of all things! Who'd have ever thought of that?? I tell you, I'm a victim of the Matrix, the likes of which you can't imagine. And no, I don't just mean this. Basically, I'm living a nightmare.

 

ibm chargers work with toshibas..........

 

Well, isn't that kind of the point of undervolting a CPU? (Although that's admittedly adjusting voltage as opposed to current) And potentiometers have existed for years, and transistors can be used to vary resistance as well, so changing resistance dynamically isn't difficult at all; the issue is figuring out the bounds for which it should be done.

Hm, so it's more of a chirping sound than a whine? A quick search turned up this article. Maybe you could try some of the solutions there?

 

The noise could also be the LCD backlight or inverter.

No they don't. And thats not relevant. Did anyone say toshiba?

Don't say stuff like that. ibm uses 20v adapters now, it would probably destroy a toshiba within seconds.

 

Wow man...quit trolling. Toshiba is already notorious with poor DC input jack design as they get pushed in alot and bottom casing destroyed.

Case in point Judy, just buy a new OEM HP AC adapter from a respectable US Ebay seller.

 

Update: just editing this to say I'll be busy for awhile attending to shipping defective items, so in the interim while I'm left in the lurch with trojan-filled, slow, tiny laptop, please bear with me.


niffcreature, that about the LCD or inverter sound like interesting possibilities, but I still need the seller (or whoever) to figure out how to get it fixed.

Thankfully, I've now switched to the thinkpad which is not whistling - yet configured with the identical hookup that the Compaq was.

Tsunade, how would changing the adapter stop the whistling?
Could I safely test an adapter from a high-powered Dell laptop with it?
Like, just for 2 min. to see if there's whistling?
The Dell states:
INPUT: AC 100-240v~1.5a(1,5a) 50-60hZ
output: dc 19.5v(19,5V) 4.62A(4,62A)
Tsunade, EDIT: This is not applicable anymore. It's being returned.

Judicator, no, I was not referring to chirping. Rather, whistling.
Trust me, the laptop was chirping too, as have other laptops.
True that's annoying, but nowhere near the whistling.

No other laptops I've used have whistled like the Compaq.
One possibility, is damage during shipment.
Another possibility, is the seller just wasn't sensitive to that high frequency, thus didn't hear it.

That's no different than those people who can eat hot mexican food, or straight vodka. Hardier bodies can tolerate hot foods, and high frequencies. (and perfume, which I can't.

Added proof:
While on the phone with Ebay's resolution representative, I placed my phone's mouthpiece to the area where whistling was emitting from Compaq, and she heard the whistling as well. It's NOT just me. She agreed it's not normal.
The WIFI should also not have caused the adapter to get burning hot.

That's another clue pointing to the WIFI as culprit, cuz you gotta believe, the whistling is the same type that was made when the WIFI was plugged in, albeit much fainter.

Have you heard of sound trapped inside ancient stones?
Have you heard of people with dental fillings hearing radio broadcasts via their fillings?

This may be the same.
Frequencies are very tricky things. Sound (and emotions) can sometimes get trapped, so who's to say that the high pitch whistling the WIFI made when I first plugged it in, didn't get trapped on silicone inside the Compaq, then keep playing in a loop?


Maybe if the guy wouldn't have shipped it to me with the card stuck inside, then everything might have been fine. But no, he just had to do it, similar to a different clown who shipped me a perfectly wonderful vintage printer, albeit with the toner still inside making a holy mess. And as if that wasn't enough, there were a zillion TEENY bitsies paper & popcorn floating all over inside the box & crannies of the printer.