Corsair HX 520W: minimum 3.3V load required?

[WhiskeyAlpha]

Hi guys,

Just wondered if anybody here knew of there was a minimum load required on the 3.3V rail of the Corsair HX 520W PSU?

I have one that I'm thinking of using as a secondary unit (I know, it sounds crazy but there's along story behind it) to my HX 620W.

The secondary unit (i.e. the HX 520W) will be powering multiple 3.5" SATA hard disks, a DVD drive, two Laing DDC watercooling pumps, 9x 120mm Yate Loon fans on a Sunbeam Rheobus and various CCFLs/LEDs.

Like I say I'm aware that the 520W unit is complete overkill for this job but the thing is I already have it. The hard disks and DVD drive should put some load on the 5V line but how much do I need to worry about the 3.3V?

Thanks in advance

[jonnyGURU]

There is a minimum load, but with the HDD's and opticals you'll be fine since their logic uses +5V.

[spursindonesia]

So, the need of having minimum load on 3.3v rail is covered with some load in 5v rail, correct ?

[jonnyGURU]

Yes. The +3.3V is just regulated off the +5V.

[Oklahoma Wolf]

I'm going to have to differ on this one - no minimum load needed. That one's indy regulated with dummy loads already installed inside it that cover all minimum load requirements.

[spursindonesia]

Now, thx for the info & clarification. So, if we're talking about a group regulated unit, any load in 3.3v or 5v rail will suffice for minimum load regulation on both of them. But specifically for an indy regulated unit with dummy load in each rail, there would be no requirement for minimum load on each individual rail. OTOH, if there is NO dummy load whatsoever, the concern of the OP would have its merit then, is that right ?

[Spectre]

I think Yellowbeard knows the answer here

But yes any load on the 5v or 3.3v will cover the minimum load requirement here.

[spursindonesia]

Hmm, it's rather confusing to me now, some contradicting opinions to digest.

[jonnyGURU]

Originally Posted by Oklahoma Wolf

I'm going to have to differ on this one - no minimum load needed.

Originally Posted by Spectre

I think Yellowbeard knows the answer here

Yep. I think we've both heard the story of his "I'm gonna use this as a +12V PSU" saga.

[WhiskeyAlpha]

Thanks for the replies fellas

Looks like there's a little difference of opinion between jonnyGURU and oklahoma wolf on whether there needs to be any load on the 3.3V/5V rails.

I understand that oklahoma wolf's opinion is based on the fact that this unit is "indy" regulated rather than "group" regulated.

I've never paid quite so much attention the the guts of a PSU since I started reading through the pages of this brilliant site and forum and I was curious where I might be able to find some more info on the difference between these two types of power regulation? (Or if one of you wanst to sling it at me in layman's terms feel free )

Not that it really matters that much, as you both agree that some load on the 5V line will be fine and the unit will always have Hard disks and dvd drives loading that.

Originally Posted by jonnyGURU

Yes. The +3.3V is just regulated off the +5V.

Is that the case with most/all computer PSUs? Or just specific to certain units?

Thanks again for the advice and being so friendly to a newcomer and kudos on the site once again jonny