so i have a Q8300 at 3GHz, GA-G31-ES2L (energy efficient series), rocketfish cooler w/92mm fan, a 120mm & 2x250mm case fans and one or two HDD's(one being a 74GB raptor) 2GB stick of 800MHz DDR2 RAM and no video card(might slip in the gt240 thats in the dell)
now this system pulls 330w under wprime 4threads(with my TX750 it pulls under 200W) and the PSU is rated for 450W with 18A on the single 12v+ rail
would this be good enough for long term use?
Re: is it good enough?
Posted: Wed May 26, 2010 4:56 pm
by skier
okay just made a HUGE discovery about PSU efficiency, will upload a video showing it shortly
Re: is it good enough?
Posted: Thu May 27, 2010 9:12 am
by Major_A
Isn't it better to get a power supply closer to what the PC is actually pulling? In terms of efficiency aren't brand power supplies actually more efficient at 80% load than 30%-40%?
Re: is it good enough?
Posted: Thu May 27, 2010 9:54 pm
by hnzw_rui
Major_A wrote:Isn't it better to get a power supply closer to what the PC is actually pulling? In terms of efficiency aren't brand power supplies actually more efficient at 80% load than 30%-40%?
Actually, I think efficiency usually peaks around 40~60%. After that point, higher temps tend to lower efficiency. The 80 Plus certification tests PSU's at 20%, 50% and 100% load. Ideally, the build will idle at 20% of the PSU's wattage. If you go below 20% of the power rating, then you can get efficiency as low as 60%. Fans on power supplies usually start ramping up at 50% load so if you want the PSU to stay quiet, you don't want to push it past 50% of its power rating.
Re: is it good enough?
Posted: Thu May 27, 2010 9:58 pm
by hnzw_rui
skier wrote:now this system pulls 330w under wprime 4threads(with my TX750 it pulls under 200W) and the PSU is rated for 450W with 18A on the single 12v+ rail
What power supply is that? I'd be more concerned about quality of the power supply rather than the wattage.
Re: is it good enough?
Posted: Fri May 28, 2010 2:56 pm
by skier
okay, was going to combine the videos but windows movie maker won't download so i just compressed and uploaded
final numbers
measured: TX750/AP-450
idle: 75w/230w
load: 130w/330w
off: 0-1w/25-26w
HOWS THAT FOR EFFICIENCY
Re: is it good enough?
Posted: Fri May 28, 2010 3:55 pm
by geokilla
How good is the Coolmax in terms of efficiency, etc. That difference is huge!
Re: is it good enough?
Posted: Fri May 28, 2010 3:56 pm
by Major_A
Just another reason to buy a power supply that won't eventually blow up in your face. I'm going to go out on a limb here and say that the TX750 is a little overkill for that setup.
*EDIT*
There I fixed Coolmax's label issue.
*EDIT 2*
I've bought this PSU for a few builds and have had great results with it. It runs quiet and has an adequate amount of connections. The only thing I've noticed with it though is the 12V rail is usually a tad on the high side. http://www.newegg.com/Product/Product.a ... 6817171031
Re: is it good enough?
Posted: Fri May 28, 2010 4:31 pm
by skier
well for standard builds im gonna go Corsair 400W from now on, $50 and a single 30A rail is solid for any mainstream graphics not to mention its corsair.
(yes i know it says $64 and $15 off, but its been at $49.99 since the first time i saw it)
and yes the 750 is overkill even for my current setup when i run a 260-250 combo(pulls 450w when both fold) but its the only decent unit i have and it was my first review back '08 so it was free ;)
i'll update with the numbers from our dell's 305W unit if i ever get to run it
