My Personal Power Supply Guide - Real World Usage

PSUs: The source of DC power for all components in the PC & often a big noise source.

Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee, Devonavar

Post Reply
Chrissicom
Posts: 22
Joined: Thu Jul 27, 2006 11:03 am
Location: Berlin
Contact:

My Personal Power Supply Guide - Real World Usage

Post by Chrissicom » Thu Jul 27, 2006 11:36 am

Hello guys :) opposite to some overclocking and loudness enthusiasts out there I am the extreme of a silent enthusiast. Silent starts for me @20 dB while this is still way too loud.
The two loudest components in my case are currently the hard drives and the power supply, so one thing to do for me is get a new PSU, but before I did some intense "wattage" testing and I want to share my results for you people and ask at the same time for PSU recommendations.

My complete system setup can be seen here: http://www.christophsackl.com/documents ... 0Setup.pdf (PDF). Here is a summary:

Asus A8N SLI Premium
AMD Athlon 64 X2 3800+
1 GB Corsair PC400 Memory
Asus Extreme N7800GT
Audigy 2 ZS
WLAN PCI Card
2x Optical Drive
2x 300 GB Maxtor SATA II

I did some testing with different real world applications to see how much power I can draw from my PSU. The PSU I use is a "be quiet! Dark Power BQT P6-520W" and the device I used to measure wattage is a simple BASETech wattage display attached to the main power plug showing current and max usage.

These are my results:

Off: 5W
Boot: 152W
Idle in Windows XP: 110W (Cool and Quiet)
Idle in BIOS: 120W (no Cool and Quiet)

1) Extreme Torture: Prime95 Small FFT (CPU), SuperPI 32M, PC Mark 2005 Graphics Test, Copy 30 GB from C: to D: and D: to C: at the same time.
Peak Power: 224 Watts (172 Watts without PC Mark 2005 Graphics Test)

2) Playing Sim City 4 with max details @1280x1024.
Peak Power: 152 Watts

3) Playing Oblivion with max details @1280x1024, 4x FSAA.
Peak Power: 190 Watts

4) Burning a DVD with Pioneer DVD-RAM drive while playing Oblivion with above settings.
Peak Power: 211 Watts

5) Burning two DVDs at the same time (one from C: one from D:).
Peak Power: 172 Watts

6) Encoding two DVDs (Gangs of New York + Fight Club) with DVD Shrink 3.5.0.12 at the same time, one to C:, one to D: with video preview.
Peak Power: 180 Watts

7) Things like playing a DVD (Fight Club) with Windows Media Player 11 (120 Watts) or Microsoft Office work (111 Watts) or Adobe Photoshop CS2 or Dreamweaver 8 work (133 Watts) don't even come close to the above tests.

I personally consider my system to be an upper class workstation (no SLI/Crossfire and not the best CPU) but still way above average for silent computing.

Well these results show that even with the most brutal torturing I can give my computer I don't even come close to 250 Watts power usage, so my 520 Watts PSU is probably overkill.
A 400 Watts PSU should easily do it, even when I add a hard disk or a water cooling right?

I thought about three alternatives for getting a new PSU.

The first would be a passively cooled Silentmaxx 400W ATX 2.0 (Link: http://www.silentmaxx.de/index.php?id=1 ... ef10144a31). The problem with this passive PSU is the "openess" so heat floats around everywhere and I still need a case fan for sure. I plan to get a Zalman Raserator Plus I so my CPU and GPU cooler would be removed and replaced by water cooling. At least 1x 120mm would be left at the rear of the case below the PSU. And probably also 1x 120mm in the front of the hard disks because I have no adequate passive cooling solution for them yet. My room temp can easily reach 30 °C btw which might be a problem as well for the passive PSU.

My other two alternatives would either be an Enermax Liberty 400W or be quiet! Dark Power Pro 430W both with cable management and an "inside" 120mm fan. What I like about this is obviously the removed unneccesary cables but there's a fan and they are both as "silent/loud" as my current PSU.

I don't like Seasonic due to the cabling, no sleeved cabling/no cable management and a fan. The "greatest" of all would be a passively cooled PSU with cable management, but I think that doesn't exist.

What do you think of the above alternatives I have listed for my system? Also do you think I should even consider a passively cooled 400W PSU with room temps of up to 32 °C?

My current temps:
Room/Ambient: 31 °C
Hard Disks: Both 38 °C
CPU: 41 °C
MB: 45 °C (my tower is open right now because the PSU is outside, the MB is around 40 °C with closed tower due to better airflow)

If you want to suggest the Antec Phantom 350W as an alternative to the Silentmaxx above... I already had this one and it was getting way too hot with an even smaller system than my current one. It was not near shutdown temps, but 64 °C is too much for my taste under 50% max. load.

Thank you very much for your assistance and also I hope some of you find the wattage testing helpful 8)

cAPSLOCK
Posts: 224
Joined: Fri Sep 16, 2005 11:06 pm
Location: Switzerland

Post by cAPSLOCK » Thu Jul 27, 2006 11:54 am

Don't forget that your wattage testing was done on wattage consumed by the PSU, not the amount put out. Considering a 75% efficiency your system was probably using around 185W at maximum load. One more nail in the coffin of the "you need 500W" myth. Well if you like modular PSU's why not the NeoHE, just make sure that you buy it from a trustworthy retailer in case you need to return it :)

You didn't mention your case, but most cases have some space above the PSU that you can shove unused cables into out of sight, out of the airflow. That's the way it's always been done before these fancy modular PSU's came out :lol:

Chrissicom
Posts: 22
Joined: Thu Jul 27, 2006 11:03 am
Location: Berlin
Contact:

Post by Chrissicom » Thu Jul 27, 2006 12:17 pm

The PSU I am currently using is supposed to have way above 80% efficiency so am I right when I say as long as my new PSU has 80+ % efficiency my measurements are good for choosing a new PSU?

My case is a Cooler Master Stacker STC-101 which is a huge cage and yes I have squished all cables in a corner, but that's utterly ugly(!) and not very helpful when you need to change something with the cabling :D

http://www.geizhals.at/eu/a174057.html < the NeoHE looks nice, but does it also generate this high pitched tone I know from my Antec Phantom? Some people don't hear it, but I dislike this TV like ultra high frequency sounds.
Do you think the NeoHE would be silent for an extreme silent freak? 18 dB in the specs sounds nice but also unrealistic. The so called 17 dB Noiseblocker Silent 120mm fans are everything else but silent although they have great reviews everywhere.
I also didn't get wether it has two or one 80mm fan?! The problem with the fan in the rear is that I can't remove the noise with case accoustic management opposite to an interior 120mm in the PSU, right?

cAPSLOCK
Posts: 224
Joined: Fri Sep 16, 2005 11:06 pm
Location: Switzerland

Post by cAPSLOCK » Fri Jul 28, 2006 1:18 am

I think you could choose any 300W PSU and it will work.

There is plenty reliable information about the NeoHE in the SPCR Review.

Chrissicom
Posts: 22
Joined: Thu Jul 27, 2006 11:03 am
Location: Berlin
Contact:

Post by Chrissicom » Fri Jul 28, 2006 3:11 am

Thanks this was an interesting read but I fear with 32 °C room temp and around 200 W load the NeoHE will definitely get too loud for my taste. The 90 W sound recorded is good, but I'd like that level of noise at 200 W.

I just called Silentmaxx about this one http://www.silentmaxx.de/index.php?id=1 ... 2a4ef3e877 and they told me 32 °C room temp are no problem and with 250 W load and a room temp of 30 °C they measured 50 °C PSU temp (don't know where they measured it). Unfortunately there are no reviews available on the usual review sites, because Silentmaxx is mostly available in Europe only.

Devonavar
SPCR Reviewer
Posts: 1850
Joined: Sun Sep 21, 2003 11:23 am
Location: Vancouver, BC, Canada

Post by Devonavar » Fri Jul 28, 2006 8:49 am

Is SPCR one of your usual review sites? We've reviewed it here, if you haven't seen it already.

david25
Posts: 89
Joined: Sun Nov 06, 2005 5:02 am

Post by david25 » Sat Jul 29, 2006 1:21 am

Hi, my FSP Zen fanless uses 25watts switched off! Whats going on?

Owen1978
Posts: 34
Joined: Sat Jun 04, 2005 12:33 pm

Post by Owen1978 » Sat Jul 29, 2006 2:40 am

How about this, its got sleeved cables!

http://www.quietpc.com/gb-en-gbp/produc ... /qt-07400f

david25
Posts: 89
Joined: Sun Nov 06, 2005 5:02 am

Post by david25 » Sat Jul 29, 2006 4:40 am

Interesting, how efficient?
Owen1978 wrote:How about this, its got sleeved cables!

http://www.quietpc.com/gb-en-gbp/produc ... /qt-07400f

jaganath
Posts: 5085
Joined: Tue Sep 20, 2005 6:55 am
Location: UK

Post by jaganath » Sat Jul 29, 2006 5:18 am

Interesting, how efficient?
It says >76%, which isn't great for a (semi-) fanless PSU to be honest. For £90 you could get a Silverstone ST30NF fanless, which has had great reviews on SPCR.

As to why your FSP Zen uses 25W when in standby mode (ie not disconnected from the mains but switched off) some switch-mode power supplies use a loading resistor for when there is no load, I don't know if the Zen PCB uses one but it is a possibility.

david25
Posts: 89
Joined: Sun Nov 06, 2005 5:02 am

Post by david25 » Sat Jul 29, 2006 5:32 am

Thanks, what about a nesteq? I had a phantom 350 and I think tthat also had high load when switched off.
jaganath wrote:
Interesting, how efficient?
It says >76%, which isn't great for a (semi-) fanless PSU to be honest. For £90 you could get a Silverstone ST30NF fanless, which has had great reviews on SPCR.

As to why your FSP Zen uses 25W when in standby mode (ie not disconnected from the mains but switched off) some switch-mode power supplies use a loading resistor for when there is no load, I don't know if the Zen PCB uses one but it is a possibility.

Chrissicom
Posts: 22
Joined: Thu Jul 27, 2006 11:03 am
Location: Berlin
Contact:

Post by Chrissicom » Sat Jul 29, 2006 7:59 am

Thanks for the review link, I've just seen it too late. Since I had very bad experience with my Antec Phantom 350 I didn't want to be dissapointed with the Silentmaxx so I bought a 430 W be quiet! Dark Power Pro now with a 120 mm fan. I am extremely happy with this product!! Not only is it more efficient than my old PSU (~84% @200 W load according to reviews) but the fan is so silent that you can't hear it spinning at 30 °C room temperature. Of course you hear the moving air but only when you have your ear on the PSU. When my tower is closed PSU noise is completely gone and also after hours of playing Oblivion which draws a lot of power from the PSU of course the fan didn't increase in speed. And also the attached fan controller is working perfectly keeping all my 120 mm case fans @ around 4.5 V. This PSU is awesome and the best I had so far in terms of silence and efficiency!!

http://www.driverheaven.net/reviews/dark_power_pro/ < this is a short review of the 530 W version, but they didn't measure it's effeciency. Considering that it is more efficient than my old PSU which had 84% @200 W I think this one is at least equally good.

My old PSU draw 110 W in idle and the new one only draws 104 W in idle. Also with the PC off it draws 4 instead 5 W (the AC Plug tool I use for measurements has an accuracy of 0.1 W).

Owen1978
Posts: 34
Joined: Sat Jun 04, 2005 12:33 pm

Post by Owen1978 » Sun Jul 30, 2006 5:19 am

jaganath wrote:
Interesting, how efficient?
It says >76%, which isn't great for a (semi-) fanless PSU to be honest. For £90 you could get a Silverstone ST30NF fanless, which has had great reviews on SPCR.

As to why your FSP Zen uses 25W when in standby mode (ie not disconnected from the mains but switched off) some switch-mode power supplies use a loading resistor for when there is no load, I don't know if the Zen PCB uses one but it is a possibility.
But on the silverstone review on the bottom of the last page...

http://www.silentpcreview.com/article185-page5.html

It shows it has effiency ratings between 76-80%

So there is no difference apart from the qtechnology one giving you 100w better option imo

Lennart Burenius
Posts: 2
Joined: Sun Jul 30, 2006 9:31 am
Location: Sweden

Post by Lennart Burenius » Sun Jul 30, 2006 9:42 am

Chrissicom wrote:this is a short review of the 530 W version, but they didn't measure it's effeciency. Considering that it is more efficient than my old PSU which had 84% @200 W I think this one is at least equally good.
I have reviewed the Dark Power Pro 600W for a swedish site. Good efficienty results, better then Seasonic S12 500W. The review is in swedish, but numbersand graphs is in universal language :wink:

Chrissicom
Posts: 22
Joined: Thu Jul 27, 2006 11:03 am
Location: Berlin
Contact:

Post by Chrissicom » Sun Jul 30, 2006 10:37 am

Thanks for the link :). I just noticed something very odd... with my old 530 W PSU I was able to get up to around 190 W when playing Oblivion. With my new PSU (the Dark Power Pro) I can barely even reach 175 W and less than 150 W is more common. How is that possible? I haven't changed any hardware or game settings except that I switched PSUs. And for a small anomaly in measurement this would be a little big of an anomaly lol :D

nici
Posts: 3011
Joined: Thu Dec 16, 2004 8:49 am
Location: Suomi Finland Perkele

Post by nici » Sun Jul 30, 2006 6:26 pm

Quite simple, your new PSU is more efficient than your old one :)

If that be quiet is like the old one the fan would run at ~5V on moderate load, and as its a 2000rpm fan it should run at something like 700rpm... :)


Oh and the correct term for 'efficiency' in Swedish is 'verkningsgrad', not effektivitet :wink: Or maybe it's effektivitet in sweden swedish.

Post Reply