Boot problems..

[MattitudeV96]

Ok, so instead of going into great detail, I'll just describe the problem...because I might have an idea of whats wrong. Basically, my computer had been acting a little funky, shutting down during times of use. Well, now, it just wont boot up. I get a no signal message on both monitors I have tried, I have an Intel 915GAV motherboard, and I have tried using both the onboard video and the video with my x800 pro graphics card. Still no signal. Everything else seems to be running smoothly inside however...could this be a sign of CPU overheatage? Or maybe GPU...? Or either one? Thanks for the info

[Sylvander]

Sylvander’s Diagnostic Flowcharts
Download a copy of my diagnostic flowcharts from here
www.erniek.eclipse.co.uk/downloads/sylvanderdiags.zip
and print them to leaf through.
Begin on the STARTUP chart.
Would I be right in guessing that you don't hear any single short beep?
If that's the case then you have...
------------------------------------------------
NO BEEP, NO VIDEO, FAILURE TO COMPLETE POST
www.pcguide.com/vb/showthread.php?t=39685
------------------------------------------------
You could start up with NO RAM and if the POST gives a warning beep, then you at least know [that it's likely that with RAM in place] the POST is running [but probably halting on some failed test that doesn't generate any beep. Failed ram does generate a beep].
The video card is only initialised toward the end of the POST, so if the POST halts before that point [or doesn't even run], then the video isn't enabled and no signal output is produced.
Hence, the monitor reports no signal received.

Then you strip back to a bare-bones hardware setup [PSU, motherboard out of the case on a non-conducting surface, CPU+fan, no switch (connect the pins with a screwdriver), no video card, no RAM].
If you get a beep complaining about the lack of RAM the POST is running.
If you get no beep, then one or more of PSU, motherboard or CPU/fan is faulty.
Fit the video and try again [should still get the RAM beep].
Fit the RAM [should be no RAM beep and POST should complete with a single short beep].
Keep adding one items of hardware at a time and startup until either the POST fails to complete, or all items are fitted and POST completes.

[mjc]

If you have tried both the onboard video and a video card...it is very unlikely that BOTH would be overheating.

[MattitudeV96]

So yeah...I started the computer with nothing, and of course got that warning beep. Added the video card, still the same. As soon as I insert the ram, no beep, no video, nothing...

[mjc]

As soon as I insert the ram, no beep, no video, nothing...

Got more RAM?

That sounds like dead or incompatible RAM.

[Sylvander]

"I started the computer with nothing, and of course got that warning beep"
Which is the good news that the POST is indeed running.

"Added the video card, still the same"
Which means the video card isn't having the nasty effect of preventing the POST from running.
[Might be having no effect at all; not connecting even if fitted, so no difference whether fitted or not. Isn't it a pity that video failure generates no beeps?]

"As soon as I insert the ram, no beep, no video, nothing..."
I take that to mean that...
The RAM tests as ok, but [possibly as early as] after the RAM test HAS BEGUN successfully [no warning beeps], something fails a POST test, and the POST halts.

Here's a generic Phoenix BIOS POST between the first RAM test and the first display...

20h 1-3-1-1 Test DRAM refresh
22h 1-3-1-3 Test 8742 Keyboard Controller
24h Set ES segment register to 4 GB
28h Auto size DRAM
29h Initialize POST Memory Manager
2Ah Clear 512 kB base RAM
2Ch 1-3-4-1 RAM failure on address line xxxx*
2Eh 1-3-4-3 RAM failure on data bits xxxx* of low byte of
memory bus
2Fh Enable cache before system BIOS shadow
32h Test CPU bus-clock frequency
33h Initialize Phoenix Dispatch Manager
36h Warm start shut down
38h Shadow system BIOS ROM
3Ah Auto size cache
3Ch Advanced configuration of chipset registers
3Dh Load alternate registers with CMOS values
41h Initialize extended memory for RomPilot
42h Initialize interrupt vectors
45h POST device initialization
46h 2-1-2-3 Check ROM copyright notice
47h Initialize I20 support
48h Check video configuration against CMOS
49h Initialize PCI bus and devices
4Ah Initialize all video adapters in system
4Bh QuietBoot start (optional)
4Ch Shadow video BIOS ROM
4Eh Display BIOS copyright notice

If any of those tests [that generate no beeps] were to fail, the POST would halt without beeps [your POST might, or might not, be different].
See any likely culprits?
A faulty video adapter might not prevent the POST from running, but be unable to be initialised and therefore halt the POST?
I've come across cases where the problem was caused by poor connections [video card or RAM], and cleaning the contacts [with Isopropyl Alcohol] did the trick.