Curse

Hsiv · Oct 02, 2010, 10:10 PM // 22:10

I'm not even sure what to title this as. After shutting down my desktop, I found the red LEDs on my front intake fan were still lit, and there was a strange clicking coming from within my computer. I flipped the switch on my PSU into the off position, but it continued. I pulled the power cord out of my PSU, but it continued. I unplugged the ethernet cable, and the keyboard/mouse, but it continued. When I unplugged the VGA cable from the back of my tower, the red LEDs went out, and the noises stopped. I plugged it back in, and it started again.

I'm not sure where to even start with this. It seems as though my computer is drawing power from the monitor, but I wasn't even aware this was possible.

What should I do?

jensyea · Oct 02, 2010, 11:36 PM // 23:36

It seems that something is broken and ticking against something else. You already found out which piece of technology is broken, because pulling it's cable out disabled the noise and putting it back in made the noise start again.

1 + 1 = 2, open it up on the side, turn it on, see what is ticking against what, replace broken part.

Don't really have to be good with computers etc. to do this sort of thing but if you really don't want to take any risk just let someone at a computer store replace it.

Hsiv · Oct 02, 2010, 11:47 PM // 23:47

Nothing in the computer itself is broken/faulty. I've looked it over several times already. The monitor is the only thing in my setup that isn't brand new. I literally built the computer myself about a week or 2 ago.

I'm thinking the problem is with the monitor itself, not so much with the hardware inside the computer. I don't have another monitor at the moment to test this with, but I will before the end of next week, so I'm hoping it's just that.

As far as I'm aware, there should be no power going into the computer from the monitor's VGA cable. Correct? Besides the monitor, nothing is plugged in to the computer. Not even the power cord.

Edit: Not much of a way to check out the monitor itself. It's a flat panel LCD, which I have literally no knowledge about the inner workings.

Edit2: Besides mysteriously powering my the LEDs and causing the noise when the computer is shut down and unplugged, the monitor works perfectly fine.

Lady Raishi · Oct 03, 2010, 02:27 AM // 02:27

i found a problem similar to yours but involved the power supply. the details can be found here http://www.tomshardware.com/forum/24...mputer-problem

jensyea · Oct 03, 2010, 02:39 AM // 02:39

Hmmm, I'm not good with computers but reason has always gotten me somewhere. As you said, your going to try plugging in a different monitor to make sure it isn't your pc causing it? That's a good idea. And yep correct, there should be a seperate cable running from your monitor to an outlet that powers it and that's all it does. Then one small cable for the sound and your VGA cable. Well, the only thing I can think off is that your monitor has some sort of adapter that charges and keeps your monitor in some sort of stand by state. Explaining the LED's. The ticking noise doesn't have to be a hardware issue by the way, I figure if the monitor has power (from what ever source that may be, it has to have power for the LED's to burn so we can assume that it does) it might as well be generating noise. Does the ticking resemble the sound a (n old) clock makes maybe? I'm just brainstorming a bit it's a really weird issue.
Hope I helped ^.^

Hsiv · Oct 03, 2010, 03:02 AM // 03:02

Raishi, that's different. In that example, there's still power coming from the power supply, and the fans are actually running. My PSU isn't even plugged in, and it's only the LEDs that are on, and the noises coming from the computer. There is absolutely no power other than the power that is seeming to come from the monitor, into the tower.

jensyea, the LEDs are on the tower, as part of the front intake fan. The monitor is plugged in to an outlet, and then only the VGA is plugged into the computer. There are no other cables besides the VGA plugged into the computer. The computer is seemingly being powered, to an extent, by power coming from the monitor through the VGA cable, which, unless I'm mistaken, shouldn't be possible.

GWfan#1 · Oct 03, 2010, 05:15 AM // 05:15

With only the VGA connected to the tower unplug the power cable for your monitor and see if those LEDs turn off and the clicking stops. If it does then maybe it is in fact drawing power somehow?

ALSO after you unplug the power supply try pressing and holding the power button for like 5 seconds, I believe right after you unplug the PSU the computer still holds a charge for a few mins and by holding the power button you are allowing it to discharge.

Snograt · Oct 03, 2010, 05:53 AM // 05:53

There's something odd going on with your monitor. There shouldn't be power coming via the VGA cable at all - just data. Maybe some sort of short, but power coming via a data cable should just fry delicate components, not illuminate LEDs and make blocky sounds.

I'm at a loss, to be honest...

What GWFan said about the system retaining a charge after power off is true (that's capacitance for you) but I don't think it's relevant, thanks to that oddness with the VGA cable.

Keep us posted!

Hsiv · Oct 03, 2010, 02:16 PM // 14:16

Just plugged the monitor back into the computer. Noises and LEDs started up instantly. Unplugged the power from the monitor, and they stopped just as fast. I'm 100% sure it's drawing power from the monitor, and not from a left over charge in my PSU. I'm' very confused, seeing as the monitor works perfectly fine otherwise...

Elder III · Oct 03, 2010, 02:40 PM // 14:40

Do the leds stay lit permanently or do they go out after a few seconds/minutes?

The best thing to do would be to beg/borrow a second monitor from someone else and test it out. Also make sure that you test a different VGA cable too. I've never heard of one transmitting power that way, but it's not totally out of the question either.

Complete system specs would be helpful too (ie brand and model of motherboard, PSU etc...)

Armageddon · Oct 03, 2010, 02:42 PM // 14:42

Never heard of anything like this

never even thought it was possible

what make and model is your monitor / gpu and do you use vga or dvi ?

Quaker · Oct 03, 2010, 03:05 PM // 15:05

There is +5volts on pin 9 of a (newer) VGA connector - I`m not sure why - so, I suppose the monitor could supply some current through that. It still doesn`t mean, of course, that the monitor is the cause of the problem. It could be that a fault in the computer`s video card is allowing +5v to leak back from the monitor - and maybe only that particular monitor.
You`d want to try both a different monitor and a different video card to be sure. It might be useful also, to remove the vidoe card and check for obvious things like bad connections in the card`s socket, loose stuff contacting the card, shorts or burnt components on the card, etc.

Hsiv · Oct 03, 2010, 03:11 PM // 15:11

The LEDs stay lit for as long as the monitor is plugged in to the computer, and it's a VGA cable, plugged into a VGA-DVI adapter, then into my GPU

Specs:
Asus Sabertooth x58 Mobo
OCZ GameXStream 850w PSU
Sapphire Radeon HD 5770 GPU
Gateway FPD1760 TFT LCD PnP Monitor (New monitor on it's way, going to try and borrow a different one for now)
Intel Core i7-930 Processor @ 2.8 GHz
6GB OCZ Gold RAM
Windows 7 x64 Ultimate OS

Wasn't sure what all you needed, so I put up everything I could think of. I'm on my laptop atm, with my desktop monitorless. Hope this helps, and thanks a lot for all of your input so far

Edit: I already looked over everything inside my tower, and nothing appears to be faulty in there. I literally went over most of it with a magnifying glass.

Quaker · Oct 03, 2010, 03:21 PM // 15:21

Try plugging the monitor into your laptop and check for smoke.

Just kidding - don`t take the chance.

Elder III · Oct 03, 2010, 05:12 PM // 17:12

Did you try a spare VGA cable? If you don't have one come over this afternoon and I'll give you an armful of 'em....

Hsiv · Oct 03, 2010, 05:18 PM // 17:18

I was going to try one about 10 mins ago, then I found out that we actually don't have ANY spares. Apparently my monitor is the only one in the house with a VGA that isn't hardwired into the monitor. It's 4 years old, and the only "new" one we've gotten for quite a while, lol. I'm going to talk to my brother, see if I can stop over at his place and borrow a VGA or DVI to test it out. I know for sure he has a ton of them laying around.

Hsiv · Oct 03, 2010, 08:37 PM // 20:37

Okay, so, I still don't know what was actually happening, but I got ahold of a DVI cable, and the problem vanished. So, I'm thinking it was a problem with my VGA cable. Anyway, the problem is gone, but no obvious reason as to why.