How much power do I really need?

[DrewSG3]

Components

1 Q9300 (maybe minor overclocking)
1 4850
2x2gb OCZ memory
1 640GB
1 DVD Burner

 

[tomoyo]

Really need? Probably 200-250w or so. However what you'll want to buy is a high quality 400W+ psu.

 

[Foxery]

400 is about right. You can leave yourself some headroom for heaviey overclocking or future upgrades, but certainly don't bother going over 500 based on what you've told us.

 

[Auggie]

haha, I bought this same setup (although with an E8400) - from the General Computing forum's guide - that thing is so helpful.

I bought an Antec 430W PSU. According to the power supply calculators I saw, that should be more than enough.

http://extreme.outervision.com/psucalculatorlite.jsp

For my setup it said that at 100% full active (ie - reading/writing to the HDD while CPU is under full load and my 4850 card rendering at full power while the mobo is accessing my 4GB of RAM at max speed and the DVD drive is spinning and playing, etc) that the total wattage was 370.

So I think you should be fine with a 430W Earthwatts Antec PSU...

Edit - Just a reminder, from what I could find, the Antec Sonata III with the 500W PSU was probably the cheapest (Newegg currently has a bundle deal going on that) and best case/PSU combo I could find, and that would certainly work well. I say this after I got a bit fancier case because I'm a fancy lad...

 

[VirtualLarry]

Originally posted by: Auggie
that the total wattage was 370.

So I think you should be fine with a 430W Earthwatts Antec PSU...

I wouldn't cut it so close. Remember, PSUs degrade with time. There's not a lot of extra room there. I would, at a mininum, shoot for a 500W EarthWatts.

 

[Pyrokinetic]

I'll second VirtualLarry's comment, because 370W is 86% of 430W. Most PSUs have a "sweet spot" of max efficiency around 50% or so of the unit's rated output, even though some quality PSUs can maintain 80+ efficiency much higher. Another concern would be fan speed and noise. Most PSUs will start ramping up the fan rpm once you pass 50% load to keep the internals cool.

So yeah, the 430W PSU may well work, but it might be rather noisy when under load. Check out the Corsair 550VX or even a 650TX; both are quality PSUs and reasonably priced.

I have a 750TX in my system, which my system will never come close to stressing even under full load -- which means it stays nice and quiet.🙂