BoonieRat said:
Are you aware that the 5 volt rail only has a high ampage (40amp) when the 3.3volt rail is at 10.6amps or less?, if the 3.3volt is above (and up to 28amp) the max 5volt is only 28.5amps.
Quote from Sparkle Specs/PDA manual
When +3.3V is load to 28A, the +5V maximum load is 28.5A
When +3.3V is load to 10.6A, the +5V maximum load is 40A
Total combined power of +3.3V & +5V is 235 watts maximum
Maximum power: 400W
Yes, I am fully aware of this. Simple math describes the relationship that Sparkle has been kind enough to show the implications of.
Power=(Volts)(Amps)
3.3+5V Power=235W
The two examples listed just illustrate what the meaning of 3.3+5v power is.
(3.3V)(28A) = 92.4W <---3.3V power
(5V)(28.5A) =142.5W <----5V power
--------------------------
3.3+5V power>234.9W
(3.3V)(10.6A)=34.98W <----3.3V power
(5V)(40A) = 200.00W <----5V power
-----------------------------
3.3+5V power> 234.98W
This is perfectly normal and expected, as we are told the 3.3+5V maximum is 235W for this particular supply. The above figures are just the natural mathematical consequences of this fact.
Don't get too hung up in specs. They are a terrible replacement for any actual knowledge of the product in question. I refer to the tendancy to take specs at face value and act on them as "psuedo knowledge". It is a trap many fall into, as few have the experience to know the actual performance and capability of the products they are comparing, and thus place the specs in their proper perspective. Basically if all we know about a given product is the specs, we don't really know much at all about it.
Going by specs alone we might be tempted to purchase say, a heavily over-rated $30 "500W" supply as it might have impressive numbers attatched to it. As well we might overlook the excellent Fortron/Sparkle supplies as they are very conservatively rated. But the truth is either the 350 or 400W Fortron/Sparkle's are amongst the most capable of PC power supplies. The nature and magnitude of the actual loads that are presented are much different than the face value assumptions most users have in regards to them. While the actual power drawn by a PC is far less than most realize, there are other dimentions to the load's characteristics to be considered. Reactance and capacitance must be understood and acounted for before any real insight into the supply's performance can be achieved.
All spec and theory aside, the Sparkle's bear the load placed on them with terrific grace. They don't have some of the things that don't really matter (multiple fans, inflated specs, or undue focus on circuit topography), but do have awesome performance, quality and value. Whatever shortcomings you might perceive in the specs of a Sparkle are really shortcomings in both the ability of simple spec sheet data to convey the reality of the situation along with a lack of understanding of the true nature of power supplies and the loads they face.
The things Diggrr noticed and mentioned concerning the situation are valid as well. Well, save one...
Diggrr said:
Most will run on a good (and by good, I mean over $60) 350 watt supply...
Far and away the best 350W supply available is the Fortron/Sparkle 350. It costs a mere $38 from directron, or 42 from newegg. But it is true that most systems (just a gnat's eyelash away from all) will run of it to great effect. It makes 220W of 3.3+5V power, quite a step up from the 185W of the Enermax 350. Quality is more important than large numbers, either on the spec sheet or on the invoice. Fortron is a huge concern, making these supplies on a huge scale in China at very economical rates. They don't feel compelled to inflate either the specs or the prices they charge. I never would have guessed before actually using the supplies at length, but they also have first class design and construction, and as such offer unmatched value. Some companies do indeed perform at a high level, and this is one of them.
It's not that specs are totally useless, and it's not that Fortron is capable of no wrong. But the simple fact remains that at present they are doing it all right. Their specs are very good, but even better is the fact that they exceed them by unmatched amounts in this industry. Take advantage.