Zalman ZM850-HP worth it for silence?

[Shadout]

I'm wondering of Zalmans 850W PSU would be a better choice than a 620HX for me.
Although both will be more than enough to handle my future system (see below), I'm not sure if the 620HX would ramp up the fan, and thus be noisier than the Zalman.

As for price, the 2 PSU's arent that different, its 15-20 dollars more for the Zalman.
So its just a matter of which one would suit me most

Build:
CPU: Q9450
MB: Gigabyte GA-EX38-DS5
Memory: Mushkin DDR2 PC2-1000 4GB CL5 Kit HP2 (2x2GB)
Hard drive: WD6400AAKS
Sound card:Asus Xonar DX
Case: Antec P182
DVD: Samsung S203
GPU: Undecided, but lets say a GTX280 for worst case scenario (rumored max TDP of 230W, although thats likely exaggerated - cooling such a card quietly represents a whole other problem, but Ill try to take one problem at a time ).

Some opinions would be highly appreciated.

[Thomas]

(rumored max TDP of 230W, although thats likely exaggerated - cooling such a card quietly represents a whole other problem, but Ill try to take one problem at a time ).

When it comes to PC and low noise, you'll get better results if looking at the whole system.

Lets assume it's correct, that that GPU uses 230 watts. The CPU should have a max. TDP of 95 watt.

For the the case of simplicity, let's say that each RAM block, DVD, sound card and hard drive uses 5 watt pr. unit. And let's say 50 watt for mobo (it's probably less).

Then we have a total of 230+95+5x5+50=400 watts.

If you OC 20%, I believe you'll end up with sub 500 watts. Going with a smaller PSU, will both be cheaper and quiter, because you stay in the load range, where the PSU got it's best efficiency => less heat => fan spins slower. And you still have power enough to the worst case GPU The saved money could be spend on good CPU cooler, like the Ninja.

If you end with such a hefty GPU, I think you should consider another case - one with better airflow. Alternatively, be prepared for modding that P182.

I dont know which case to suggest, but I have the P180, and with a 50 watt GPU and a CPU with maybe 50-60 watt, then I had to remove the doors in front of the fans, in order to get enough airflow, and keeping it reasonably quiet.

[Shadout]

I'll fix the filters in the front, and have a kama bay as intake, not much else.
Going for either TRUE-120 or Xigmateks cpu cooler, should be more than enough I think (only added the actual power using hardware in my post ^^).
Would obviously add a third party cooler to GPU as well.

Not sure if its enough airflow in the P182 :/
It is certainly an issue if it cant keep components cool, but then again, others around here has made builds with 2x GPU's in a P182 :O

About the PSU efficiency, according to Mike's review of both the 620HX and the ZM1000-HP (cant find numbers for the 850w), the Zalman actually has higher efficiency.

Still, this isnt a concern about power, I know the 620HX got more than enough to power anything I'll ever use!
Its purely a question of which of them will be most quiet.

You are of course right in the end its the noise from the whole system which matters, but I have to start out somewhere Quite impossible to figure out the noise from GPU's which is not being sold yet. When I know more about those I can take a final decision.

However, even with a more moderate GPU, it seems likely you would reach the higher fan speed on 620HX.

I know everyone are in love with the Corsair PSU, and I'm close to getting it too, I just have to wonder if its mostly the perfect PSU only for computers drawing less than 300W (which is what most people got around here I guess), due to its smaller fan.

[Thomas]

Deleted, sorry.

[Erssa]

Not sure if its enough airflow in the P182 :/

This is highly subjective. Some people have insane arbitrary temperature goals and thus need the best coolers and insane amounts of airflow. Some settle for stability and can run their computers quiet.

It is certainly an issue if it cant keep components cool, but then again, others around here has made builds with 2x GPU's in a P182 :O

And that's probably because these people have higher tolerance for temperature readings.

Going with a smaller PSU, will both be cheaper and quiter, because you stay in the load range, where the PSU got it's best efficiency => less heat => fan spins slower. And you still have power enough to the worst case GPU The saved money could be spend on good CPU cooler, like the Ninja.

About the PSU efficiency, according to Mike's review of both the 620HX and the ZM1000-HP (cant find numbers for the 850w), the Zalman actually has higher efficiency.

Yes, this "lower power psu is more efficient" is pretty much a myth, if you exclude the picoPSUs. The only good reason to stay away from high output models is their price, but given how excellent Zalman ZM1000-HP and ZM850-HP are, it's really hard not to recommend them for high power setups.

I strongly disagree with Thomas. Going with Corsair will result in a louder computer at every load, SPCR graphs speak for themselves. Zalman ZM1000-HP @ 400W is quieter then Corsair at 40W load. Spend the extra money on Zalman. It's pretty much the best investment you can make on a silent high power system.

[Shadout]

Thanks for the input.

About temperatures, I have a high tolerance, as long as it doesnt burn down... and is not drastically reducing the components lifetime, its not too hot So that is good to hear.

[krille]

So will the ZM500, ZM600-HP, ZM750-HP and ZM850-HP stay as quiet at 400W load as the ZM1000-HP will (as seen here)?

I very much want that ultra-quiet at 100W higher load headroom. But I hardly need 1kW. 600W would probably be more than enough.

edit:
I get the impression from Zalman's site that ZM1000-HP and ZM850-HP are the same, while ZM750-HP, ZM600-HP and
ZM500-HP are made of slightly different components (the cooling specifically). But what about their noise levels?

[aSASa]

I'd imagine the lower watt PSUs make more noise at equal wattages.

AKA, the 1000 watt might be silent at 500 watts while the 500, 600, and 750 will be loud. Basically due to cheaper cooling components inside. For a perfect example of cheapness from a change in watts, look for inside picture of a Cooler Master 850 watt and the 750 watt [ Real Power Pro ]. Its unbelievable!

[krille]

I'd imagine the lower watt PSUs make more noise at equal wattages.

AKA, the 1000 watt might be silent at 500 watts while the 500, 600, and 750 will be loud. Basically due to cheaper cooling components inside. For a perfect example of cheapness from a change in watts, look for inside picture of a Cooler Master 850 watt and the 750 watt [ Real Power Pro ]. Its unbelievable!

Or Seasonic's 330w vs 380w.

Anyway, the 1kW and 850W seem to have similar if not identical interiors, they should perform the same, no? (See links in my previous post.)

[Erssa]

So will the ZM500, ZM600-HP, ZM750-HP and ZM850-HP stay as quiet at 400W load as the ZM1000-HP will (as seen here)?

I very much want that ultra-quiet at 100W higher load headroom. But I hardly need 1kW. 600W would probably be more than enough.

edit:
I get the impression from Zalman's site that ZM1000-HP and ZM850-HP are the same, while ZM750-HP, ZM600-HP and
ZM500-HP are made of slightly different components (the cooling specifically). But what about their noise levels?

AFAIK, this PSU is based on some pre-existing Enhance ODM model. They offer a range of 800W to 1200w in the series -- hence the Zalman 850W model. The heatpipes are used in Zalman's 600W model, but that one is made by Fortron -- and FSP has always had dumb linear fan controllers, and it's not as efficient.

Only the 850W and 1000W models are really silent.