Old motherboard, new power supply - no power?

Hi, I was moving a P5W DH Deluxe with Core 2 Duo E6700 processor, 8 GB of RAM, a Radeon HD3870x2 and a SoundBlaster X-Fi Fatality to a new case, and giving it a new power supply. I did not originally put the system together, this is the first time I have tried to connect everything myself. I have a Corsair HX620W that I've set up now, I thought properly, but when I press the power button I get nothing.

I have tested the power supply using a paper clip and it starts, and powers fans, etc. I connected the EATXPWR connector, the 4-pin power connector, and also the system panel connections. When the system wouldn't power on I flipped the system panel connections the other way (since there was no instruction on whether I should have the label side up or down) but it didn't do any good.

What could be the problem? How do I troubleshoot this? I have no POST card, so I can't go that route...

8 answers Last reply
More about motherboard power supply power
  1. I would start off by going through this checklist:

  2. Ok, I re-set all the power connections, found a description of how to tell which direction to place the system panel connections, and tried it again - I now have a green LED and power when I hit the power button. However, I don't get any system beeps, and I have no video.

    I have a Radeon HD3870x2, I plugged in the 6-pin power connection. I don't have an 8-pin power connector that will fit the 8-pin connector on the video card, could this be a problem? The red LED on the card is lit, however, so I think it has power too.

    Thanks again in advance!
  3. You need to plug in both power connectors to the GPU. The red light on the GPU means it's not getting enough power IIRC.
  4. I guess I'll have to get an adapter - I don't have an 8-pin power connector on this power supply that fits properly :( The rounded and square pins/sockets don't line up :(
  5. The 620HX should come with 6+2 pin PCI-E connectors. They should be a 6-pin connector with an extra 2 pins that can be connected to make it an 8-pin connector.

    How long have you had the 620HX? I just did some more checking and I guess some of the early ones didn't come with the 6+2 connectors. If you really don't have the connectors, I think Corsair will send them to you. You really should have the 6+2 connectors since you said you were adding this PSU to your existing system. Double check the modular cable bag.
  6. +1 short ...


    corsair web site show that you should have 6+2 pcie connector.
  7. Yeah, I have it - I'm an idiot. I never thought of adding two together.

    All is well - I have POST and can get into CMOS, now I just need to set up my storage drives.

    Thanks again!
  8. HAVE FUN !!!
Ask a new question

Read More

New Build Power Supplies Power Motherboards Systems