Did I really get two bad PSUs?

Hi guys,

So I recently ordered parts to build a new, rather cheap computer. My original order for the PSU was a DiabloTek 550W PSU. When I got it, as well as my other parts, I started installing them into my case. Due to my case's design, I had to remove the internal fan at one point to install the mobo panel into the side of the case. I realized, afterwards, that I didn't remember how the fan was originally situated, so I figured I'd power on the fan and see which was it was blowing. My PSU, however, wouldn't turn on the fan - in fact, it didn't seem to turn on at all. It's own fan didn't kick in, and it wouldn't supply power even when the mobo and graphics card were also attached. I tested two of the Molex leads with a multimeter, and got no voltage across the leads, so I figured I got unlucky and picked up a dead PSU.

Due to how I ordered the DiabloTek PSU, TigerDirect told me they'd just give me a refund for the purchase, so today I went to my local Fry's to pick up a new PSU so I could finish building today. I picked up a 600W Coolmax PSU. It, however, has the same issues as the DiabloTek - it doesn't seem to power on when plugged in, won't turn on my fan (even when other components are also plugged in), and doesn't seem to have any voltage across its leads.

Did I really manage to pick up two bad PSUs? Or am I doing something wrong? Should I just completely build my machine, and then it should work? Anyone have experience with either of these two PSUs, or know better tests for them?

5 answers Last reply Best Answer
More about psus
  1. Best answer
    Check the toggle switch in the back of the coolmax to be sure it's on. Also try a bare post on a phonebook or motherboard box. Just the cpu/heatsink, one stick of memory, video, and keyboard. Use both the 24 pin and 4 pin power supply leads. When everything is set, touch the power switch pins with a flathead screwdriver to power on. At the post screen, enter the bios and set the boot order (ex.-floppy, cd, hardrive), set the memory voltage manually if needed, save and exit with f10.
  2. Did you not get the memo about how crappy those no name PSUs are? Get a quality unit from Corsair, OCZ, Antec, or PC Power.
  3. I'll try doing that setup and startup, o1die - thanks! The Coolmax PSU at least seems to make a hum when I plug it in and turn the back switch on - so something must be going on.

    Shadow703793 - I did look up reviews for both of these units before I purchased them. They both seemed pretty good (at least serviceable), and it's looking like maybe the fault is with me. I'll let you know how o1die's setup goes - and certainly if both don't work in that setup, I'll go get a more name-brand PSU to try again!
  4. ^If you read the Newegg reviews that would have been a problem. Read real reviews here:

    In either case, I highly recommend you get a quality PSU ASAP, because those two PSUs WILL die on you, possibly taking some thing else with it. It's just a matter of time.
    ^That's a CoolMax btw.
  5. Turns out both work fine. I'm not sure why, but they wouldn't show any signs of life until I hooked the motherboard up to the case's power switch and then turned it on that way. I went with the DiabloTek one and returned the other. Thanks for all your replies, and yea I'll probably switch out the DiabloTek sometime soon to be safe. Probably after I move (which should be soon). Thanks again for all your guys' help.
Ask a new question

Read More

Power Supplies Fan Components