You should not have used that old supply. That connector is the ATX12V
connector, which is the main power supply for the CPU.
On some motherboards, it's the only connection of power to the CPU and
the system won't run (at all) without it.
In other systems, the ATX12V socket is still jumpered to the main 20-pin
(or 24-pin) connector, and the system will run but may be unstable.
Presumably, your motherboard is in this category.
There are a number of possibilities here, ranging from no damage at all
to destruction of the motherboard and/or CPU (you could also have
"blown" the interconnection between the ATX12V connector and the main
20-pin connector within the motherboard foils .... which although it
sounds bad, might simply mean that from now on, ONLY a power supply with
a "real" ATX12V connector will work).
You will just have to try things to see what the damage is. Starting
with a new power supply.
hot july wrote:
> About three weeks ago my power supply went out on my Asus mobo (p4s533 or
> something like that). The asus mobo had a 4-pin cpu power connector from the
> psu going to it. Well I had a spare psu that had no such 4 pin cpu connector
> but I put it in anyway and the computer ran just fine. It's been running
> fine for almost a month. Yesterday I turned comp on and got the "no signal"
> display on the monitor, which suggests a cpu or psu problem to me. The mobo
> does not beep when powered on either. No, nothing wrong with video card or
> hdd. I need to know what, if any, damage could had been caused to the cpu by
> not running the 4 pin power connector to it? Seems to me if there was a
> problem, it just wouldnt boot, sort of like now
But it did run fine for
> three weeks without the connector, so I don't get it.
>
> A link to the pic of the 4 pin connector is below if you need to know for
> sure what I am talking about.
>
>
> http://i10.tinypic.com/29kwduq.jpg
>
> 
>
>