Just blew up something in my pc and now no boot - whats broken?
January 7, 2007 10:48 AM Subscribe
Just blew up something in my computer, now it won't boot. What steps do I take?
Okay so I just tried to push a USB dock into my PCI usb port. The computer shut down and acrid smoke started coming out of the back. I switched it off at the plug. No flames.
Now I've plugged it in, rebooted and no go. I've removed everything but the mobo/processor, power supply, ram, and graphics card, it still won't boot. What can I do to figure out what is broken? (besides buying new parts). I guess it could be the mobo, processor, RAM or graphics card. The fan in the power supply is working, as is the one above the processor. HELP!
PC details:
PC Chips M848A
1 Stick of cheap ram
2 internal HDs
APG Graphics card
PCI TV Card
PCI USB (4)
Okay so I just tried to push a USB dock into my PCI usb port. The computer shut down and acrid smoke started coming out of the back. I switched it off at the plug. No flames.
Now I've plugged it in, rebooted and no go. I've removed everything but the mobo/processor, power supply, ram, and graphics card, it still won't boot. What can I do to figure out what is broken? (besides buying new parts). I guess it could be the mobo, processor, RAM or graphics card. The fan in the power supply is working, as is the one above the processor. HELP!
PC details:
PC Chips M848A
1 Stick of cheap ram
2 internal HDs
APG Graphics card
PCI TV Card
PCI USB (4)
If the motherboard seems to be ok, you could try getting it to boot using a different power supply if you have one handy. Other than that... you might want to see if your hard drives are alright, especially if they contain anything important.
posted by benign at 11:06 AM on January 7, 2007
posted by benign at 11:06 AM on January 7, 2007
Does the computer beep when you switch it on? Most mobos have 'morse' codes when something is broken. Sounds like you blew something on the mobo as well.
Most mobo will do a self check and create some output even without RAM or even a CPU.
posted by homodigitalis at 11:17 AM on January 7, 2007
Most mobo will do a self check and create some output even without RAM or even a CPU.
posted by homodigitalis at 11:17 AM on January 7, 2007
Response by poster: no beep :(
Mobo must be dead. This is irritating. I don't really want to risk buying a new one if its not the motherboard.
posted by tomw at 11:24 AM on January 7, 2007
Mobo must be dead. This is irritating. I don't really want to risk buying a new one if its not the motherboard.
posted by tomw at 11:24 AM on January 7, 2007
Use your nose. Sniff everything. The problem will be where the stink is.
posted by popcassady at 11:29 AM on January 7, 2007 [1 favorite]
posted by popcassady at 11:29 AM on January 7, 2007 [1 favorite]
Take it apart - everything, even the mobo out of the case. Things that give up their smoke leave marks: blown caps, scorch marks, etc. Cant find anything? re-assemble and try to boot without the vid card. Even without onboard video, the machine will still try to post and, if everything is works, will beep. If so, get a new video card. It goes without saying that you should ensure that your system speaker is properly plugged into your mobo before trying this.
What should you NOT do? Although it seems counterintuitive, don't bring your setup to a friends house and swap parts in and out. I did this after frying something in a P2 machine many years ago. Brought the setup to a local PC shop, who ended up frying two more processors in their attempt to figure out what part of my setup was fried :(.
posted by datacenter refugee at 12:32 PM on January 7, 2007
What should you NOT do? Although it seems counterintuitive, don't bring your setup to a friends house and swap parts in and out. I did this after frying something in a P2 machine many years ago. Brought the setup to a local PC shop, who ended up frying two more processors in their attempt to figure out what part of my setup was fried :(.
posted by datacenter refugee at 12:32 PM on January 7, 2007
Hold on - just to clarify, you were installing a PCI card in a powered-on machine?
posted by aberrant at 12:50 PM on January 7, 2007
posted by aberrant at 12:50 PM on January 7, 2007
and I think I misread your dilemma. You were plugging in a USB hub to a USB port that existed on a PCI card that was already installed, right? First thing I'd check is the power supply.
posted by aberrant at 12:54 PM on January 7, 2007
posted by aberrant at 12:54 PM on January 7, 2007
Sounds like the power supply, which shouldn't cost more than $30-40 to replace.
posted by dropkick at 1:36 PM on January 7, 2007
posted by dropkick at 1:36 PM on January 7, 2007
If the fans *are* working, it shouldn't be the power supply. Are the HD's powering up too?
posted by edjusted at 4:06 PM on January 7, 2007
posted by edjusted at 4:06 PM on January 7, 2007
Modern PC power supplies are grunty as hell, and quite capable of putting out board-destroying amounts of current into a short circuit before they shut themselves down.
Also, your equipment list screams "low end, budget-built, thrown-together PC" to me, and machines of that nature often suffer from assembly slackness that makes PCI cards sit badly in their slots when their mounting bolts are installed, which in turn makes them susceptible to moving around when you plug stuff into them.
It seems likely to me that you've shorted out one or more power rails in the PCI slot that the USB card was plugged into, probably damaging the card, the slot, and the motherboard.
Popcassidy and datacenter refugee are quite right about being able to locate the magic smoke's escape point just by looking and sniffing, but you really do have to have all the parts you're sniffing bare out there in the air before your nose can sort out where the stink is originating.
posted by flabdablet at 1:13 AM on January 8, 2007
Also, your equipment list screams "low end, budget-built, thrown-together PC" to me, and machines of that nature often suffer from assembly slackness that makes PCI cards sit badly in their slots when their mounting bolts are installed, which in turn makes them susceptible to moving around when you plug stuff into them.
It seems likely to me that you've shorted out one or more power rails in the PCI slot that the USB card was plugged into, probably damaging the card, the slot, and the motherboard.
Popcassidy and datacenter refugee are quite right about being able to locate the magic smoke's escape point just by looking and sniffing, but you really do have to have all the parts you're sniffing bare out there in the air before your nose can sort out where the stink is originating.
posted by flabdablet at 1:13 AM on January 8, 2007
Response by poster: Thanks guys. Most of this is spot on.
I've taken the opportunity to upgrade mobo, processor, RAM. Does the power supply hold any danger for the new components?
edjusted: I figure the power supply is okay since the fans are working?
posted by tomw at 5:33 AM on January 8, 2007
I've taken the opportunity to upgrade mobo, processor, RAM. Does the power supply hold any danger for the new components?
edjusted: I figure the power supply is okay since the fans are working?
posted by tomw at 5:33 AM on January 8, 2007
If you can get your hands on a digital multimeter, you can test the power supply (or have it tested).
(Previously: I posted instructions on backprobing an ATX power supply.)
Another (often overlooked) diagnostic tool is your keyboard. (This is probably a moot point now, but I'll add it for posterity.) Very early in the POST sequence, the keyboard lights (CAPS, SCROLL, NUM) will flash. Take notice next time you turn on your PC if you've never noticed this before.
The KB flashes occur before the PCI and video card tests (and the "no video" beep sequence). This can offer an additional clue as to where the system is failing. If the KB lights up, then the power is good (enough), the CPU is good, the memory is good (enough), and the problem is occuring somewhere down the line.
posted by edverb at 8:30 AM on January 8, 2007
(Previously: I posted instructions on backprobing an ATX power supply.)
Another (often overlooked) diagnostic tool is your keyboard. (This is probably a moot point now, but I'll add it for posterity.) Very early in the POST sequence, the keyboard lights (CAPS, SCROLL, NUM) will flash. Take notice next time you turn on your PC if you've never noticed this before.
The KB flashes occur before the PCI and video card tests (and the "no video" beep sequence). This can offer an additional clue as to where the system is failing. If the KB lights up, then the power is good (enough), the CPU is good, the memory is good (enough), and the problem is occuring somewhere down the line.
posted by edverb at 8:30 AM on January 8, 2007
This thread is closed to new comments.
posted by Krrrlson at 11:02 AM on January 7, 2007