Black screen while PC boots

I just cleaned PC (well CPU fan only), and i turned PC on but forget to insert CPU 4 pin wire (not the first time). Unpluged PC from electiricty. I inserted it and turned on PC, then the CPU cooler started to spin like crazy. Windows loaded and cooler started to work normally but motherboard temperature was 60 C. I restarted the PC to check BIOS settings, but the screen was black, no beeps, hard disk were spinning as if there were loading windows, i tried to reset BIOS setting but no affect just black screen. DId i damaged the motherboard. I forget that i was playing minecraft on built in graphics card (20 - 30 fps, yes i know bad, but i wanted to play so much). Maybe video card is dead?? please help! Specs that I remember:

Motherboard: HP P4SD
CPU Intel Pentium 4 2.80 GHZ
Ram 1.5 GB DDR, (1 GB + 256 MB + 256 MB) - Kingston
Built-in video card: Intel (R) 82865g

Edit
I have re-seated the RAM but look what happened:

RAM

Little Helper

Posted 2011-08-03T14:19:15.630

Reputation: 1 906

2When you forgot to connect the 4-pin CPU power, did you turn the computer off before plugging it in? – Darth Android – 2011-08-03T14:22:24.643

@Darth Android Good Question! – Sandeep Bansal – 2011-08-03T14:25:21.230

There are quite some specifications missing. Can you give a more full list? The frequency of your CPU or amount of RAM are unlikely to help us, while the type of motherboard and similar details can help us tell what you can try to troubleshoot. Start by double checking everything, in the worst case you might need a new GFX card or motherboard. – Tamara Wijsman – 2011-08-03T14:26:01.350

@Darth Android yes i turned off the cable, inserted 4 pins, then I turned on PC, the CPu fan runed like crazy, after windows started the CPU fan returned to original speed, but my motherboard temperature was higher tah 60C so i restarted pc and there this black screen apiered. please help – Little Helper – 2011-08-03T17:23:53.137

Sory, since my PC can't run, I can't give you my specs. but all components (ram, video card etc) runned good, i think i messed something with power or motherboard, because when i plug pc to eletricity it automaticli turns on, what does that means? – Little Helper – 2011-08-03T17:28:37.843

Well my PC tries to boot, i hear HDD drives spinning and black screen, after few sec. of booting computer freezes, numlock; scroll lock etc. arent responding, even power button dont work – Little Helper – 2011-08-03T17:32:25.750

possible duplicate of Black Screen when Computer Boots

– ChrisF – 2011-08-03T17:53:15.747

nope, not a duplicate – Little Helper – 2011-08-03T17:54:36.387

Im online back again. How? My memory sticks: 2x 256 MB are not working any more on my system but what's the heck, I still got 1 GB stick :) – Little Helper – 2011-08-03T18:45:09.667

Try to turn it off, pull that power cord out again, and re-seat it. – KCotreau – 2011-08-03T20:26:08.977

Answers

Judging by that picture, the fact you're using an integrated video adapter, and your remarks about sticks of RAM not working, I'd say you have bad RAM.

Get Memtest86+ (or another competent RAM tester) and run it against the RAM sticks, one at a time, for many hours (we do 48 hours of testing before declaring a RAM module as "passed").

This should help you identify which stick(s) are bad. If they come up clean after 48 hours on each stick, then I think you'd be at a point where you need to start swapping in known-good parts to find the culprit (RAM modules, motherboard, PSU, etc.).

Ƭᴇcʜιᴇ007

Posted 2011-08-03T14:19:15.630

Reputation: 103 763

When you cleaned out your PC you could've had some dust moved in critical areas, take another look at it and make sure there's no dust or anything trapped in the PCB of the motherboard, also try and locate where the integrated Graphics is, if you provide the model of your motherboard I can help further. Not putting your CPU Fan wire in could have caused the CPU to heat up but shouldn't have caused any damage since the heatsink was placed on top.

What I would suggest your do is give it another once over.

Sandeep Bansal

Posted 2011-08-03T14:19:15.630

Reputation: 6 168

If the computer was only on for a minute or two before you realized the CPU fan wasn't spinning, and then you turned it off, no damage is likely. I did the same thing once, but was able to run Windows just fine. The temperature did start rising but since I shut it down before it got too hot, no damage was done. In my experience, a temp in the 60s isn't a problem in the short-term, but definitely don't let it get higher. – Ben Richards – 2011-08-03T18:06:06.733