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I bought a thrift store Compaq Presario to use its power supply and case for a project.
It has a power switch on the back, but the front power switch attaches to the motherboard (which is now in the trash).
I need the power to be controlled only by the switch on the back.
After looking at AT power supply pin diagrams and experimenting I determined that connecting the PowerGood (Orange) line to the -5v (Grey) line does the trick.
Does anyone have any tips or gotchas to share?
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Hi PIEBALD,
PIEBALDconsult wrote: connecting the PowerGood (Orange) line to the -5v (Grey) line does the trick.
that does not sound right at all, in many ways.
According to some documents (Google!) the "power good" signal is an output from the
power supply, which becomes high to tell the motherboard power is good enough to start up
(hence release the /RESET input).
If the control line is a pseudo-digital one, it should either be pulled high, or pulled
to ground, never negative.
Normally I expect you need to connect a SENSE input to the corresponding voltage output
(that is 3.3V SENSE to 3.3V; or 5.0V SENSE to 5V on older systems). The sense feedback
should occur on the motherboard, as close to the highest load as possible, it is intended
to achieve a well regulated voltage at that location, independent of voltage drops along
the cables/PCB tracks due to varying currents.
In conclusion, maybe you interconnected the right pins, but I doubt the names you
mentioned apply; and anyhow, if one of them is a sense line, the connection should be
next to the actual load, not right at the power supply.
So I suggest you check the documentation again, and possibly throw a multimeter to it,
to make sure voltages are what they should be.
Regards,
Luc Pattyn [Forum Guidelines] [My Articles]
this months tips:
- use PRE tags to preserve formatting when showing multi-line code snippets
- before you ask a question here, search CodeProject, then Google
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Hi,
the fourth link tells us ATpsu should work without any special wiring.
didn't it work for you with PG open?
the second link suggests "power good" is an output which goes high when everything
has stabilized, as I expected. So connecting it to -5V seems a bad idea.
And I trust you read about the minimum load required (around 0.8A).
Luc Pattyn [Forum Guidelines] [My Articles]
this months tips:
- use PRE tags to preserve formatting when showing multi-line code snippets
- before you ask a question here, search CodeProject, then Google
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Most sources say that the AT PSU has the front switch connected directly to it, whereas the ATX has the front switch connected to the motherboard; this particular one seems to be an in-between design; newer than AT, older than ATX.
I'll mention that it also has another connector for the motherboard with three green and three black wires, which (from what I read) seems to be for PCI cards?
Luc Pattyn wrote: And I trust you read about the minimum load required (around 0.8A).
I skipped it until I read your earlier response. 
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It might be a nonstandard design like the dell PSUs from that era, in which case you'll need to track down maker specific data. IIRC the standard (but rarely used) 1x6 extra power cable provided 2 different voltages as well as ground.
--
If you view money as inherently evil, I view it as my duty to assist in making you more virtuous.
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I've now connected the -5 to ground and it seems to be working fine.
If it goes "poof" I'll let you know.
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Why do you insist on short-circuiting something? the purpose of the -5V output pin is to
provide a voltage of -5V with respect to the GROUND pins, and not to be short-circuited.
Maybe it will survive your abuse, but it does not have to. And maybe it will solve your
problem, but it does not have to either.
The only thing you should do is provide some load to the +5V (i.e. between +5V and ground)
in such a way that at least 0.8A is flowing all the time. A 5 to 6 ohm resistor should
do the trick, but be careful it will heat up and must be strong enough to dissipate
4 to 5W (current*voltage) so it cannot be a regular .25W or .5W resistor, it would have
to be one of those wire-wound resistors (about 1 inch long, 1/3 inch thick).
Alternatively you could attach a light bulb (as from a bike's or car's head light),
that too would (have to) heat up a bit, again dissipating some 5 Watts.
What also is supposed to work is just connecting an obsolete motherboard, whatever is on
board will need a couple amps.
And whatever you do, once everything has been set up, I suggest you actually measure the
voltages you plan on using, before you use them, since after your experiments I am not
that confident your PSU is still OK...
Luc Pattyn [Forum Guidelines] [My Articles]
this months tips:
- use PRE tags to preserve formatting when showing multi-line code snippets
- before you ask a question here, search CodeProject, then Google
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Vibrator of my Nokia 6600 is not working properly for 3 days, does anyone one know how to troubleshoot that.
Best Regards,
Mushq
Mushtaque Ahmed Nizamani
Software Engineer
Ultimus Pakistan
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Mushq wrote: Vibrator of my Nokia 6600 is not working properly for 3 days
I don't want to know how you broke it. It could be because of over-use.
Mushq wrote: does anyone one know how to troubleshoot that.
Does it vibrate? No? It's broke.
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Shut down/close the phone, boot it up again; see if it reset the vibration.
Toggle on and off the vibration mode, just in case.
Reset the phone ( there must be a reset menu somewhere ) to the factory settings.
if it does not work, pay a visit on one of the howard chui forums (google for howard chui ), maybe someone can help you.
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Maximilien wrote: Shut down/close the phone, boot it up again; see if it reset the vibration.
Toggle on and off the vibration mode, just in case.
Reset the phone ( there must be a reset menu somewhere ) to the factory settings.
I tried, but these didn't work. 
Maximilien wrote: if it does not work, pay a visit on one of the howard chui forums (google for howard chui ), maybe someone can help you.
Thanks for that, I am going to check that.
Best Regards,
Mushq
Mushtaque Ahmed Nizamani
Software Engineer
Ultimus Pakistan
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Fundamentally it's a small motor with an off-balance weight attached to the shaft. It will eventually fail.
DoEvents: Generating unexpected recursion since 1991
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It's most likely that the motor itself has gone. It's an individual component that sits into the main housing so a full disassemby but no soldering is required.
Pop along or post to your nearest Nokia Care point (you'll find them on your countries Nokia web site) and they will fix it for you, shouldn't cost much.
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Hi all,
I wanted to enquire about a topic which just came into picture in our organization...
We all know that adding RAM increase the system performance..but upto a certain extent after that adding RAM starts affecting the system performance.I intend to know that point after which if I would increase the RAM my system performance will go down.
Currently I am using Dell Optiplex GX745 Desktop with Pentium D 3.40 GHz and 1GB RAM.
Regards,
Dhawal Seth
Software Consultant
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Going from 1 dimm per channel to two dimms per channel will result in a very slight performance decrease because the second dimm will require the memory controller to use slightly looser timings. IIRC all P4D systems are dual channel so that would be going from 2 dimms to 4. Going from 2 to 3 would result in a major hit since the with the nonsymetric memory you'd end up running in single channel mode.
The capacity of the dimms has no bearing on this, and if going from 2x512 = 1gb to 4x1024=4gb allows you to reduce/eliminate your swap file usage the gain from that will dwarf the hit from memory timings.
--
If you view money as inherently evil, I view it as my duty to assist in making you more virtuous.
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Hi,
I have this motherboard and an Realtek RTL8187 Wireless 802.11g onboard wireless card. However, it couldn't seem to be able to detect our home wireless internet signal? Anyone experience the same? TIA!
I am a SysAdmin, I battle my own daemons.
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If it can't connect to an existing network, my guess would be that your motherboard's NIC
a) doesn't support your router's features
b) is misconfigured
c) does have the (latest) motherboard drivers loaded
d) is defective (entirely possible).
Without a lot more info regarding your router and NIC configuration, that's the best I can offer.
"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001
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hai friends,
one of my friends (electronics guy) had the following doubt. since iam a software person, i could understand nothing out of it. and i thought that, this forum attracts the professionals, who can answer this question.
the reply would be more appreciable and helps him a lot in his career.
his mail is as follows.
We need to add three more instructions for a microprocessor i.e., I33 and I17 and I9 to the existing design. the instructions I33, I17 and I9 regquired 33, 17 and 9 CPU cycles to execute individually. For example, a 32-bit restoring division takes 32+1 cycles to produce the right result, this is the motivation behind I33. Our task is to add the instructions, I33, I17, I9 to the existing design. The new design shall handle multi-cycle controls and using ROM for storing the micro-program. The divider control signals can be "straw ones".
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and the question is...
--
If you view money as inherently evil, I view it as my duty to assist in making you more virtuous.
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Our task is to add the instructions, I33, I17, I9 to the existing design. The new design shall handle multi-cycle controls and using ROM for storing the micro-program. The divider control signals can be "straw ones".
may be this one.
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If you're asking about how to design hardware you're on the wrong board. I don't have a clue where you should be posting, but CP is a software development forum. This subforum is for issues with setting up hardware for deploying apps or for interfacing with hardware programmatically. You might see if the IC design software you're using has a support forum.
--
If you view money as inherently evil, I view it as my duty to assist in making you more virtuous.
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I see
but i have googled regarding the hardware design forums but in vain.
thank's for the reply.
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Where's the "existing design"? The statement of the problem doesn't make any sense without the necessary background information. Anyway, this looks suspiciously like a homework problem. If you have a specific question you can ask it, but don't ask us to do your work for you.
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This is certainly not a homework question,
but this came from one of my friends who is already working in a company.
please refer to my original post.
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