Have: 350 watt rated motherboard Need: 400 watt power supply Can anyone help?

Question

My mother board (which I am NOT replacing) is only rated, (and only works) with 350 watts or less. How do I use a 400 watt video card with this system. I am willing to buy anything, cost is not a concern, but I would like to keep it as low as possible. No I will not buy a new computer. PLEASE keep the computer jargon to a minimum, it gets kind of annoying.

Could anyone help me?

Answer 1

Bigger power supplies usually run cooler and gives you elbow room for other upgrades. Thus, a 400W, 430W, 450W, etc. will all work. Any of them will just provide what is being demanded by the system, nothing more.

Powerful video cards usually have their own power connectors. They just draw data from the motherboard but source their power directly from the power supply through the PCIe power connector.

Answer 2

The wattage of a power supply doesn't matter, so long as it has enough wattage to power the system.

The power supply supplies power at certain voltages. Devices will draw the wattage they need. For example... a 60 watt light bulb will draw 60 watts and a 100 watt light bulb draws 100 watts... They'll both work fine because there's over 1000 watts available from the socket...

Actually... If the mainboard recommends 350 watts for the entire system and the video card is recommending 400 watts for the entire system and the specs aren't saying these devices actually draw that much on their own... Something like a 400 or 500 watt power supply should work great. It sounds like this is what's going on here. I would go with the 500 watter so you don't have to worry about installing additional hard drives, etc...

Answer 3

Ah, that's not how it works. A 300 Watt power supply is capable of powering up to 300 watts of devices. For example, a 30watt motherboard (which is typical) two hard drives at 10watts (typical under load), a video card (varies quite a bit so let's say 50 watts) and other peripherals like RAM (say 20 watts each x 2). This means your total load would be about 120 watts or so. Of course, this can vary under load so a 300 watt supply is capable of carrying the whole load at 50% of its rated capacity.

If you MB requires a 300watt power supply it means that it consumes quite a bit of power--as much as 3 100 watt light bulbs and would make your system very difficult to keep cool. That's 10x the normal load. Frankly, I've never heard of a motherboard that consumes that much power short of one on an IBM 370 165 mainframe.

If you have a video card that consumes a lot of power (and some do), you'll need a somewhat larger supply. As I said, 300 watts is a medium to large supply--400 would be catagorized as "large". I've seen a need for these bigger supplies on systems that have lots of drives, rams and fans... but often it's overkill.