Asus A7N8X; PSU ATX 1.3 and 2.3

[Peterg2]

Hi,

I am about to build one and perhaps 2 new computers. My current main computer is an ASUS A7N8X Deluxe which was using an Antec Truepower 430 whose rails were starting to sag.

I knew I needed immediately to replace it and with the view to my imminent build I bought a Corsair HX650 which while theoretically an ATX 2.3 unit is backward compatible to 2.01. My MB is ATX 1.3 using the 5V rail primarily. This works fine now in the computer.

However, for my new build I started thinking I would really rather have bought the Seasonic X 650 Gold series. My thinking was I would return perhaps the Corsair and eat the 15% restocking fee.

However, when I installed the Seasonic X650 today it starts, the fans including the CPU fan spin up and it goes nowhere. No beep, no boot, no video.

I bought this online and I don't have a new motherboard to test the Seasonic on. I will be get an Asus X58 board.

Is this most probably a case of simple incompatibility? Or is the PSU defective? I know that I am asking a lot but how often do you people run into similar incompatibilities like this? I really do not want to RMA a perfectly fine PSU. I am about a week or two away from purchasing parts for my new system(s)

Any ideas most appreciated.

 

[Peterg2]

Part of the puzzle has fallen into place. I have an old Iwill KK266 Plus box lying around which was used as a fax server. Hooked it up and it boots fine into Windows.

So, either there is something about my A7N8X which it does not like or despite several attempts I am not fully hooking up the 20 pin connector.

 

[ComputerWizKid]

I had an Asus A7N8X and I believe that board requires the -5V line which newer PSU's do not have anymore. The K266 board probably needed the -5V line but was not required to function.

 

[Peterg2]

I had an Asus A7N8X and I believe that board requires the -5V line which newer PSU's do not have anymore. The K266 board probably needed the -5V line but was not required to function.

Thanks very much for your reply which made me think about this afresh. Here is a thread which indicates that it was not needed with the A7N8X:

http://www.techsupportforum.com/har...1032-power-supply-requirement-asus-a7n8x.html

So far, I was advised on the NCIX forum that it most probably was the fact that the +5V rail was not strong enough on the X650. It provides a maximum of 25 Amps and a total wattage of 125 Watts which is shared with the 3.3V rail. My old Antec Truepower 430 was a lot stronger on the 5V rail.

Here is the thread:

http://forums.ncix.com/forums/?mode...did=2186062&pagenumber=1&msgcount=4&subpage=1

I will probably pull the trigger on my new system build with an Asus X58 MB in the next 10 days.

Do you feel the thread above encapsulates the problem or not? Would you go ahead and RMA this PSU just in case?