Plug PSU in, fan cycle for 2-3s, then turn off, cycle again, computer won't boot

By TeamworkGuy2
Dec 1, 2010
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  1. My problem is almost identical to this thread http://www.techspot.com/vb/topic121358.html
    I am putting a new video card (HD 4650) into the system in my sig.
    Uninstalled drivers, put new card in, plugged in power supply and the CPU and GPU fans started for 2 to 3 second, than stoped, started again and stopped, they continued to cycle on and off without me ever pressing my cases power button.
    I had to put the power cord the get the fans to stop cycling.
    Then I removed the video card and the booted the computer using the integrated graphics and everything worked fine.
    Is the start up power draw from the video card is to much for my Dell 305w PSU? Maybe the PSU can't supply enough power, which would explain why removing the card fixes the problem.
    I tried removing two of my computer's four RAM stick and reinserting the video card, but the fans would still endlessly cycle until I pulled the power cord.

    What should I do?
    Should I get a new power supply?
    I measured the current PSU and it is a weird size:
    ~3 7/8" tall (9.8 cm)
    ~5 1/2" long (13.8 cm)
    ~6" deep / width (14.7 cm)
    Voltage and such... 305W
    +5V = 22A
    +12VA = 18A
    +12VB = 18A
    -12V = 1A
    +3.3V = 17A
    +5VSB = 2A
    combined max 12VA and 12VB = 22A

    I saw this PSU... at newegg
    Any help, comments suggestions? Do you think it really is the psu or am I barking up the wrong tree?

    P.S. I just noticed that the HD 4650 box and newegg page recommend a 400w power supply, so I guess the power supply is the problem.
    My old card was a X300, would the HD 5450 have equivalent power consumption?


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