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Mobo replaced but the PC does not start

By orangext88 · 12 replies
Nov 21, 2011
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  1. hello everyone.

    im new to the site, and new to the hardware side of computers (genuine noob).
    my brother in law had an old alienware desktop sat in his garage unused due to some components being fried. i decided to take on the challenge of repairing it for my own use as a gaming machine.
    apparently the graphics card died and my bro in law took it to a pc shop and they said something else had fried too.
    ive had the pc open and had a little nosey around but everything appears to be ok. started the pc up with everything as it was. sounded as though it ran fine but no picture on the monitor. this would confirm the graphics card being ruined. i tried a different graphics card in the pc and got a message on the monitor about the frequncy being wrong ( i honestly cant remember what it said). any how, going on what my BIL (brother in law) said, i thought replacement mobo and processor.
    had a look on ebay and managed to find the exact replacement mobo, cpu, that came with 2 sticks of mem and a graphics card. total cost £22.50.

    specs as follows:
    MOBO = D865PBZ intel
    CPU = pentium 4
    mem = is apparently 1GB
    graphics card is unknown

    this is what i received today in the post. brilliant. so straight to work on replacing the parts. original mobo and cpu out. the replacement ones with mem and graphics card went in. i hooked up all the components incl... 2 x hdd, 1 x cd/dvd drive, and a floppy drive too.
    powered the machine up and 2 seconds later it switched off. Gutted. so i start to trawl the web for how to fix the issue. and i get some info.
    i have unplugged all components including mem and graphics card.
    powered on again. i get 3 long beeps. checked the manual. missing 64 bits of memory. so from what i learned from my little research now plug in the ram. so 1 ram went in. powered on. still no other components attached and 3 secs later it turns off again. tried both ram sticks seperately in all dimm slots. still same 3 sec problem. tried some kingston ram sticks and same problem. 3 secs and off. remove the ram and power up. 3 long beeps but pc still runs. another suggestion i read is heatsink and fan not sitting right or connected properly. put the original heatsink/fan on the replacemnt mobo it is attached correctly and plugged in correctly.
    i have not tried the original mobo and cpu yet with the new graphics card recieved so i dont know if the original set up works. but i know that used to run until i turned it off. even though there was no moniter picture.

    im sorry for the long *** explanation. like i say im a noob. so if i take you through how i did it then you may know where i went wrong. i ensured my arm was touching the pc case at all time when handling the components so i believe they are not fried from static. the replacement parts off ebay. the seller said he had the set up running in a test rig using unbuntu, and he said it was all working fine. so have i done something critically wrong??
    if any one has any suggestions then please let me know. i would appreciate it very much. i hope to get this problem resolved asap.

    many thanks

  2. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,231   +234

    There are so many things that can go wrong with this... Make sure the motherboard is not shorting to the case. Did you clean off the old paste and apply thermal paste between the CPU and it's heatsink? Did you attach the power supply 4-pin (12v AUX) connector to the connector near the CPU socket? The 3 long beeps are normal when the memory is not installed, and you must remember to at least install memory in the slot closest to the CPU. The 3 beeps give me hope that the motherboard is okay...
  3. orangext88

    orangext88 TS Rookie Topic Starter

    hi thanks for the reply. i have not got any thermal paste but the heat sink fan is secured in place. and the 12v plug is plugged in. but as soon as i place a memory stick in. it closes down 3 seconds later. could the ram be wrong for the board??
  4. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,231   +234

    Oh so the heatsink and CPU were already installed on the motherboard? This replacement motherboard is the exact model as the original board? If so, the memory should work
  5. orangext88

    orangext88 TS Rookie Topic Starter

    yes exact replacement. i got it from ebay. it arrived with cpu + heatsink attached in place and ram sticks in their dimm slots. i still have the original components so im going to have a play around with some parts. i finish work in an hour so i will have all day. erm if you need more information let me know and ill try my best to get it.

    another note. the original mobo and cpu ran. no shutting down after 3 secs. but with no graphics card i was unable to check the monitor to see where the boot up proces was at. aybe i should of popped the gpu in the original to see what state that was in.

    any way thanks for the reply.

  6. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,231   +234

    Okay play around with some parts and tell us what you discover ;)
  7. orangext88

    orangext88 TS Rookie Topic Starter

    hi again. im getting somewhere. i have installed the original mobo and cpu but with the new gpu. it runs and it gets to a black screen that states. 'a disc read error occurred. press ctrl + alt + delete to restart'
    i presume this is a good screen to get in a way as its all going somewhere but now this disc read error is stopping it from starting. i have restarted it numerous times but nothing. i have had a little search online for a fix and its something about getting windows recovery console. any ideas.
  8. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,231   +234

    You may have to format the hard drive and re-install Windows fresh...

    "a disc read error occurred"

    This may also indicate that the hard drive is dying, but attempt a format first
  9. orangext88

    orangext88 TS Rookie Topic Starter

    i dont have a windows disc. i believe its a hdd windows job. the serial key number is on the pc case. will formatting wipe the windows off it.

    edit: just got of the phone with my bro in law. he said that the hdd's are in a raid format. hes has a floppy disc for drivers. so i have to wait till tomorrow to get them. could this be what is causing my current problem. as i removed the mobo it wiped the bios settings and memory. it could explain it not being able to read the disc.
  10. orangext88

    orangext88 TS Rookie Topic Starter

    ok i have received pretty much everything that came with the comp (manuals, xp discs, raid floppy).
    found out the reason for disc read error was in bios, raid was disabled. changed to enabled and the pc loaded up all the way to login screen. logged in and it all appeared to be fine. restarted computer loaded up to login screen again, went to log in but computer requested windows setup and serial key confirmation. i wasnt hooked up to net so i had to shutdown and transfer the tower to the other side of the room so i could hook up an ethernet cable. powered up and the pc started doing that stupid 3 seconds on then turning off thing. tried some previous steps and it still did it. got angry because i was tired and the mrs was nagging so i removed all power and took out bios battery. put it back in and it started running again. did post and it loaded windows then the screen went black. monitor displaying out of range. i presume the video settings need changing???
  11. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,231   +234

    You need to get this computer in good operating condition before you set up RAID again. Set the bios to IDE and format a single drive. Install Windows XP make sure the computer is stable. Once this is done, you can add additional drives and initialize a RAID array
  12. orangext88

    orangext88 TS Rookie Topic Starter

    yeah probs better to start from scratch. noob qeustion again. how do i format the hdd without going into windows. do i do it via system recovery??
  13. Tmagic650

    Tmagic650 TS Ambassador Posts: 17,231   +234

    Boot the computer with the XP CD. When it gets to the installed Windows list, delete the install listed and do a quick NTFS format. Let the install finish

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