Bringing up a GTX 460 host

archae86
archae86
Joined: 6 Dec 05
Posts: 3145
Credit: 7024764931
RAC: 1810864

RE: Power consumption While

Quote:
Power consumption
While the manufacturer of this GTX 460 card recommends a system power supply of over 500 watts, I'm entirely comfortable with my supply vs. consumption situation, and suggest that a merit of the GTX 460 over truly high-end GPUs for BOINC use is the likelihood that many users would find themselves not needing an upgraded supply, not heating their rooms so much, and paying a good deal less to their utility over the life of their system.


Urmm... maybe not--regarding the adequacy of my Nexus Value 430 supply.

I have from time to time seen more than one symptom with this system that might suggest power supply deficiency. But I hung to my belief that what I had should be plenty, with heavy reliance on the Kill-a-Watt report that I was using far less than the specification limit of my supply.

The new element that kicked me into action was a power display that updates more rapidly (and perhaps averages over an even shorter interval relative to update frequency). Specifically, as part of checking out a newly purchased UPS destined for my main desktop machine, I plugged this system into it, and was shocked to see that the power output displayed fluctuates madly. With an update rate of roughly three values shown per second, in less than a minute I see values from 135 to 324 watts. As these are output from the UPS, and thus input to the system power supply, and the capacitors in the power supply must smooth things somewhat, I have to presume the dynamic range on the 12V outputs is yet more. As the Value 430's 12V portion is only specified for 33A or 396W maximum, and the conversion efficiency in this range is supposed to be very high, and worse yet it is specified as a 4-rail design, I no longer think my position of confidence in the margin on this supply for this application is remotely warranted, and regret having provided advice to others here which, if followed, may have contributed to WU errors, system reboots, and the like.

As I continue to value low acoustic noise, as my next try I've again ordered Nexus, but this time the NX-6000, which in the 12V section of interest specifies a 50A single-rail maximum, rather a substantial boost from the 33A 4-rail spec I've been running under. When it arrives, I'll try some of the higher CPU task + GPU task conditions which gave me elevated WU error rates in an attempt at direct comparison to generate evidence of power supply culpability.

As of now, I don't believe the power supply issue compromised the productivity numbers I posted in message 116664, as for those I relied on the elapsed times for successful WU completions, but I'll recheck that point as well.

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.