Power Supply Question

[Stealthrida]

Hey guys new to this forum. Anyway i have an older computer a SOny Vaio PCV-RS 431X anyway i decided to upgrade my graphics Card to a Nvidia BFG 7300GT. I ended up buying it and not noticing i didnt have enought power for the car mine is a stock 293 wats. I bought a BFG 550 power supply plugged it in and the computer did not turn on, after checking everything i realized that there was a wire that doesnt come with the power supply its a 3 pin female that connect to a 3 pin male on the motherboard i guess to turn on the comp? So idk if i did something wrong or someting i can find the wire im looking for like a converter from 4 pin to 3 pin female molex it has to have 3 wires.

 

[diduknowthat]

Your motherboard has a 3 pin male connector that needs to be connected to the power supply? Isn't that the fan connector? Just leave it unconnected and see what happens.

Also, your old power supply should have powered the card, the 7300gt isn't exactly a high performance card.

 

[Backwoods166]

Did you turn on the PSU, there is a switch on the back. Did you accidentally unplug the power button from the motherboard? Recheck all wires to make sure they are blugged in. 3 pin? It does sound like a fan, these should plug into your mobo not your psu. Look for it labled as "system fan" or "power fan" on your motherboard.

Is it the same kind of plug as your 20+4 pin connector just a 3 pin? If it is then your going to have to do some modding on your 4 pin power connector. But, I have never seen a 3 pin =/

 

[Stealthrida]

I left the 3 pin unplug and the computer did not turn on. I check over the wiring and nothing everything was done right the switch on the back was on the comp just did not power on. The 3 pin that connect to the 3 pin male look like the one for the disk drive.

didyouknow--- The box says it needs at least a 350 W power supply, mines only a 293. The wire connecting to the 3 pin i thought was for the fan which looks like it. I bought a 4 pin to 3 pin but it was 2 wires instead of 3 and it never turned on so im not sure what to do anymore.