Inability to boot PC, troubleshooting ideas

So, I've had this HTPC box for a bit, and decided to upgrade it to be able to play HD content. Previously it had a 2.0ghz P4 (512/400mhz) and was able to play basically anything that was below HD resolution (could do 540p).

So, I checked out the compatability of the machine and chose a processor known to be compatible to upgrade to. In the end it was a 2.8Ghz prescott P4 (1024/533mhz). The difference in speed should be enough to allow it to play fine.

Install it, lo and behold, the machine refuses to boot.

So I am asking you, the DCEmu populous: What might the problem be?

This is the motherboard: http://www.asrock.com/mb/overview.as...45GV%20R5.0&s=

and the processor (again) is a 2.8GHz, 1MB Cache, 533Mhz FSB Pentium 4 Prescott.

Things I have already tried:

Upgraded the BIOS to the newest revision.
Made sure to connect a fan to the CPU's fan plug (sometimes that may be checked in order to boot).
Tried detatching all other devices to see if it might be a power issue.
Tried booting with only a single ram stick (with each of the two installed).

Tried booting with no ram, in which case, I still don't get any sort of POST beep codes, and my POST card still gives the same error.

The only things that I could possibly think may be the problem are:
1) The processor is bad.
2) The motherboard isn't actually compatible with the processor.
3) The power supply can't handle the demand on the 3.3v line

It is still working fine with the old 2Ghz, but isn't fast enough to play HD content, which is what I wanted to upgrade for.

Any ideas as to what could be wrong?

I don't think this is much help to you but I think it's just a compatibility issue (although I can't guarantee it I'm no expert in CPUs). If you want to be sure, try getting a replacement or try using a similar chip from the same manufacturer from a friend or something.

Another thought that's highly unlikely but possible is the power supply isn't supplying enough power for everything to run properly? I think that the CPU runs at full load (100%) until an OS is loaded.

Edit: Lol I just noticed everything I stated you already previously said, sorry.

Quote:

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Originally Posted by quzar

The only things that I could possibly think may be the problem are:
1) The processor is bad.
2) The motherboard isn't actually compatible with the processor.
3) The power supply can't handle the demand on the 3.3v line

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Be more specific does the computer Post, are you able to get into the Bios, is it just a black screen? Are there any beeps from the motherboard speaker, if so whats the sequence?

make sure you are pushing the power button. I add that because some times my grandmother calls and asks me why her computer wont boot. YOU'RE WELCOME!

Quote:

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Originally Posted by Cap'n 1time

make sure you are pushing the power button. I add that because some times my grandmother calls and asks me why her computer wont boot. YOU'RE WELCOME!

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LOL thats something my grandma would do.

Hahaha, old people are great.

The old bloke (late 80s) who lives next door went out and bought a PC because his typewriter broke :)

After a cpl hours of trying to slowly explain the concept of files and folders to him, I set it up to boot straight into a blank office document, showed him how to print and turn the thing off.
100s of letters to his relatives in Europe later and he still has no concept of saving/loading/starting a new document. :)

Quote:

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Originally Posted by BrooksyX

Be more specific does the computer Post, are you able to get into the Bios, is it just a black screen? Are there any beeps from the motherboard speaker, if so whats the sequence?

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I suppose it was a bit circuitous, but I did say that after taking out all ram, the machine still gives no post beep. It seems that I omitted the bit where I had written that I used a seperate POST card which gave me only a special code that indicates either all working fine or motherboard not starting at all.

So to more specifically answer your questions:

The computer does not POST at all, neither through beeps, via an external POST card, or to a video output (tried builtin vga, then agi through dvi, vga, and composite).

To VideoFreak, yes, at the moment I am suspecting that the power supply may be insufficient. The only evidence to the contrary is that my POST card does not indicate any problem on any of the voltages.

Have you tried jumping the bios and resetting them back to default. I accidentally set my vcore to high and my mobo did the same thing. After using the jumper it went back to normal. Um how old is the motherboard? Ever thought the mobo battery went dead? Had you reciever any CRC checksum errors in past when booting up?

Quote:

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Originally Posted by jedikevin20

Have you tried jumping the bios and resetting them back to default. I accidentally set my vcore to high and my mobo did the same thing. After using the jumper it went back to normal. Um how old is the motherboard? Ever thought the mobo battery went dead? Had you reciever any CRC checksum errors in past when booting up?

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I have cleared the CMOS multiple times (after changing settings using the working P4 2.0), this has not resolved the problem. The battery works fine and has never cleared the CMOS on me without me trying. The motherboard is maybe 3 years old. Again, never had any problems with corrupt CMOS/RTC problems.

Quote:

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Originally Posted by quzar

I suppose it was a bit circuitous, but I did say that after taking out all ram, the machine still gives no post beep. It seems that I omitted the bit where I had written that I used a seperate POST card which gave me only a special code that indicates either all working fine or motherboard not starting at all.

So to more specifically answer your questions:

The computer does not POST at all, neither through beeps, via an external POST card, or to a video output (tried builtin vga, then agi through dvi, vga, and composite).

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Oh okay, I read over too fast the first time and I didn't really put 2 and 2 together. Sorry :p

My guess would be that either the cpu is no good or that the mobo and cpu really arnt compatible even though the manufacturer says they are.