View Full Version : PC won't post

14-01-2003, 12:42 PM
I have a prob similar to this (http://pressf1.pcworld.co.nz/thread.jsp?forum=1&thread=28068), however the solution there doesn't work for me.

Gigabyte ga-7zx, athlon t-bird 1ghz, 512 ram (2 x 256 sticks), leadtek geforce 3. Problem is that the pc won't post on boot. On a normal boot the geforce will post first, then the pc, but nothing appears on screen. There are no system beeps when attempting to boot.

I have removed each of the ram sticks to no avail. I have inserted an ISA vid card to no avail (although I didn't remove the geforce at that time, maybe I should; would the system default to agp as primary?).

The weird thing is that this has happened before, but each time I had assumed that it was the chip temp sensor preventing a cold boot when the cpu was too warm (set to 60 degrees in the bios). After leaving it overnight the pc always started with no probs the next day. The pc has always started from a warm boot, only cold boots have been a problem before.

At this stage, I'd prefer not to have to replace (buy) anything until I have a definitive diagnosis. Any suggestions?

14-01-2003, 01:02 PM
Are you saying that now it won't boot from both warm and cold boots?

From what you've said it doesn't seem as if you've recently done anything different, but you could always try (and I know this seems a stupid answer) leaving it to cool down, booting it, and turning off the BIOS setting that shuts down the computer if it's too hot. I've got a Gigabyte mobo, and it's set to shutdown if it reaches (from memory) 90*C.

Does the HDD light on the front of your PC case flash to indicate HDD activity? And do you hear all the normal sounds of your PC booting, only not see anything on the screen, or by "won't post on boot" do you mean it won't run the POST (Power On Self Test) process?

14-01-2003, 02:21 PM
It would seem that the only thing you haven't tried is the AGP card. In my experience thses can cause all sorts of problems if they're not seated correctly. Try pulling it out the re-seating it nice and firmly.

14-01-2003, 02:34 PM
Oh yes, I forgot, my Gigabyte mobo came with a nasty black plastic clipon device, designed by Intel, around the AGP slot, supposedly to hold the card in properly. Much to my avail, it did the reverse, and stopped my AGP card from being seated properly as part of it interfered with a component on my video card - they were obviously never designed to accomodate the TV decoder chipset, which takes up a fair bit of space.

After reading the manual for this device, aimed at retailers, I discovered you put it on by pressing it down firmly over the slot, and it clipped in place underneath the edge of the slot. This made me think I would never get it off, but my dad discovered, it snaps apart at one end (I was left wondering why the manual for it didn't just say "snap it open, affix around AGP slot, and close it").

So yes, your AGP card might not be seated properly, and I'd try taking it out and putting it back in with and without the Intel device (I don't use it, and never knew about things like it before, and I've never had troubles with a card coming out of its slot).

14-01-2003, 02:48 PM
does the mainboard have 4 diag leds at the back panel?

Terry Porritt
14-01-2003, 03:38 PM
I suppose it could be a bad connection or a short somewhere, or horrors, a crack in a m/b track causing an intermittent fault. Try reconnecting all connections including power cables at m/b, re-seat all cards. Loosen screws holding motherboard just in case there is a short at the m/b stand-offs.

14-01-2003, 05:10 PM
OK, I've eliminated the vid card - still no post with a known good pci card.
I've eliminated all other add-in cards (nic and mpg)
I've eliminated the hard disk (currently backing up in another pc - whew!).
I've eliminated the monitor.
I guess that only leaves the mobo :(

Any suggestions as to what would be a good replacement? AMD, currently have sdram, but something that can handle ddr as well would be good. Or other fixing type possibilities.

Terry, am about to remove mobo from case and see if that makes any diff.

14-01-2003, 05:24 PM
If you're going to buy a new mobo, ASUS is a known trusted brand, and I'd say they're the best out there.

This mobo (http://www.asus.com/prog/spec.asp?m=a7s266-vm) might be good, it has 2x DDRAM and 2x SDRAM, but I'm not sure just what kind of AMD processor you have.

These are a few mobo brand pages for AMD processors:
ASUS (http://www.asus.com/products/mb/overview_amd.htm)
Gigabyte (http://tw.giga-byte.com/products/socketa.htm)
ASRock (http://www.asrock.com/product/amd/index.htm)

14-01-2003, 06:07 PM
Athlon T-bird 1Ghz

I'm officially declaring the mobo dead - have removed everything including the cpu and it still won't post. Time for a new one :(
Only got about 20 months out of it too :_|

14-01-2003, 06:11 PM
It happens sometimes. X-(

My dad once had a mobo ready for a slimline case, put it in, and it went "phut" and never worked again. :^)

14-01-2003, 06:17 PM
> I'm officially declaring the mobo dead - have removed
> everything including the cpu and it still won't post.

Fair go, how could you expect it to POST (Power On Self Test) without a CPU. ;)

The CPU is needed for any mobo post, as there is no intelligence on the motherboard to execute the code contained in the bios code.

A bios chip failure could also cause this. Another posting some months ago had this effect, needing to warm the bios chip with a hairdryer first. Usually terminal though, as many bios chips are soldered into the mobo.

14-01-2003, 06:25 PM
>The CPU is needed for any mobo post, as there is no intelligence on the
> motherboard to execute the code contained in the bios code.

Really?? I didn't know that.... so it could still be that I've fried the cpu? I did notice that the heat paste had kind of melted and run so that there was none directly on the chip but some around it ... if you get my drift.

14-01-2003, 06:38 PM
Oh dear...

Perhaps you should see if you can borrow a CPU to test with before you dosh out for a mobo? Or junk the lot, as you may have 2 discrete problems?

Remember dont even think of firing one up without full heatsinking on, as it will die real quick.

Its not possible to run any code, even that required to do a POST, unless there is something to understand the cose, and execute it. On power-up, the CPU gets a Power_Good signal from the Power Supply, then does a reset and loads code at the default address, which is the BIOS initialisation code. No CPU, no nothing.

I am unsure about the Graphics card, as they do contain a "GPU", but doubt they have the intelligence to run a POST by themselves, I think it would be under the command of the CPU

14-01-2003, 06:52 PM
Bugger ..... would someone with a gf3 like to completely dismantle their pc and see if it will post only with the vid card in ?? :) :) :)

14-01-2003, 07:07 PM
> On a normal boot the geforce will
> post first, then the pc

Also I *think* you are mistaking the difference between POST and BOOT.
You will be unlikely to see the results of a POST on the screen, as it is before it even knows it has one in most cases.

Thats why motherboards are fitted with diagnostic LEDs, or beep codes from the on-board speaker. You see the results of a BOOT operation, which is what it does after a successful POST.

If a graphics GPU does its own internal POST of the graphics adapter, its also unlikely to tell you, it wont be displayed?

I wait to be contradicted on this.....

Terry Porritt
14-01-2003, 08:10 PM
Before dumping the motherboard try testing it 'on the bench' ie out side the case on an open surface where you can get to things easily.

AT motherboards were a bit easier to test out on the bench with a spare power supply, but you can also do this with your ATX unit. The psu will probably have to be removed from the case together with the soft power switch to do this, so that the leads will reach the m/b.

Probably your Athlon heat sink had a thermal pad which 'melts' under the action of heat and the force of the heat sink clip, so that only a microscopic film is left on the cpu. If you replace the heat sink, remove all trace of the existing stuff and recoat with a thin film of thermal grease.
Quite a bit of force (16-24 lbs, about 10kg) is needed to fit the clip, so you have to be careful.

It would pay you to test the board again with just the cpu, video card and memory, and check to see if you get a beep.

If you do get a beep, then things are looking good, and you could carefully re-assemble it all in the case and try again.

14-01-2003, 10:08 PM
Tried that Terry, no cigar there either. What gets me is that there are no beeps whatsoever, regardless of what's in or out.

16-01-2003, 02:31 PM
An update for those of you following this.

Tested the cpu in another mobo (offsite) and it was fried. Have now bought and installed a new mobo, cpu and ram.

16-01-2003, 03:07 PM
Wonder how it got fried?

Anyway, hope your troubles end here.

24-01-2005, 08:03 AM

I have a bit of the sam,e problem, I have everything hooked up right, everything sounds and feels like a normal boot, but I can't get it to post.

Hardware is working, most of it is new. I think the problem may be my vid card, but even then I can't get hte speaker to beep at me. I am sure the jumpers are set correctly.

amd 1500 cpu
asrock k7v4a+ mobo

any ideas??


24-01-2005, 08:44 AM
Start your own new thread and give a few more details.

This was started over a year ago.