I'm in the middle of building my new pc and I'm a bit stuck what PSU I'll need. Spec is as follows:
BIOSTAR TA990FXE Motherboard
8gb Kingston HyperX 1600 DDR3 memory
AMD FX6100 bulldozer CPU
SAPPHIRE HD6750 2GB DDR3 Graphics Card
WD 1TB 7200rpm HD
Arctic Cooling Freezer 13 CPU Fan
Generic 12cm Fan *2
1 SATA Sony DVDRW
1 SATA Sony DVD Rom
According to Sapphire, if i crossfire their card I'll neeed 600w just to power the card
Arctic say I'll need 200w to fire the fan and Biostar say 300w to power the MB
That's a lot of juice!
Can anyone give me a more realistic figure? I'm not into major gaming. Just the usual GTA, Sims etc. Mainly going to be used for CAD design etc.
Realistically a 600w-750w psu would be good and give you some head room to oc...
sapphire said xfire 600w... they are including your basic build plus the two cards in xfire
mobo wont consume 300w by itself, most likely with everything hooked up to it
and the atric cooler will not consume 200w...
You're reading those power requirements wrong. When Sapphire says 600W, they mean for the system. Although I find it hard to believe/understand why they recommend that considering that a 6750 has a TDP (maximum power draw) of 86W.
When Arctic says 200W TDP, it means that it can effectively dissipate 200W of heat from the CPU.
I don't know what Biostar and the 300W is about. But a motherboard doesn't use anywhere near that much power.
So the major power consumers in your build will be the CPU, which has a TDP of 95W and the GPU. Which totals 181W. Add 50-100W to account for RAM, HDDs, fans, optical drives, etc. And that is being very rough and probably overestimating what those components combined will ever use.
Even a high quality 300W PSU with a 6pin PCIe connector would be able to power that build fine. If you are looking to crossfire then 450W+ with two 6pin PCIe connectors.
More if you want to overkill, can't find good deals on the lower wattage models or want the option to upgrade to more power hungry video card(s) in the future.
If you want some specific recommendations then providing your budget and a link to a site that you are using or a list of models available to you would be useful in allowing others to make a specific recommendation.
Manufacturers don't know if you'll buy a crappy PSU that's only half as powerful as advertised or a quality one. Your system will run fine on a quality 400W PSU. The PSU calculator will help you determine how much power is required to crossfire.