new motherboard 1

[alex304]

I just purchased a new motherboard cpu and memory. I was going to try to use the old power supply. The motherboard is a PCChips M851G and has a 3.3v Core voltage connection. My power supply does not have this connector. The computer will not turn on. The power supply fans turn...but I do not get any beeps. Do I need the 3.3v connector? Could this be why my computer won't start????

Thanks.

 

[macphoneguy]

My .02 Cents, if your old power Supply does not have the physical connector to attach to the motherboard, you need to get either another PS or a Adapter, if it is physically connecting 2-3 things come to mind 1 is looking at the mainboard and seeing if there are any jumper/dip switch's related to Power, and everything else match's i.e. dimm/simm the right speed/size, 2 any Cards in the I/O Slots needing reseating or something else

 

[alex304]

There's a main power connector which I've connected to the mother board. Then there's the 3.3v connector which only has 4 contacts...I've ordered a new power suppply last night with this 3.3v connector on it. I am just hoping this is the problem or I'm out $250.00 (cost for new part that currently aren't working). The new power supply should be in in less than a week. I was just hoping someone knows what this connector is for and if it's necessary. I've checked the PCChip website...but it really bites.

 

[Freestone]

The four-pin connector (J3 according to page 13 of the manual I downloaded) is an auxilary 12V connector and is required in order to provide the 3.3V to the CPU.

A couple of sites explaining this, amongst many:

http://www.informit.com/articles/article.asp?p=31105&seqNum=4

http://www.pctechguide.com/tutorials/MBoard_Power.htm

I don't suggest trying anything else with this PC until you get the correct supply. I don't know if any damage has been caused by trying to turn it on without this connector. Maybe someone else can comment on that.

 

[alex304]

Thanks,

I will wait for the new power supply to get here. After reading the info on these links, I think that this is all I need.

 

[jurgen36]

I dont know your particular mainbord. However I found in many instances that by not connecting the 12 volt high current plug to the mainbord the system will not start up at all. Also in some cases tracks on the main bord running to the 3.3 volt regulator section burnt out. So you might be lucky but it is also quite possible that you need a new main bord. Your chances are about 50% that all will be well. Good luck.

Jurgen