*****Official***** DFI NF4 ultra-D first look

[mrlobber]

You have already seen the board has the ability to run Vdimm off the 5vline. What you don't know is that i found heat became an issue with the dimms on load at high voltages.The mosfets have heatsinks and you are going to cool them for stability. I have chosen to tweak the 3.3V line up to 3.6V on my powerstream and this allows 3.5Vdimm or so and does seem more stable for me.

So for, say, 3.6Vdimm you still need the 3.3v line of the PSU to be tweaked higher than that?

[Bennah]

So for, say, 3.6Vdimm you still need the 3.3v line of the PSU to be tweaked higher than that? "Yes" or "no" would suffice.

What's the point then on the ability to switch the Vdimm voltage to be powered from either 3.3 or 5v line, by user selection, as Oskar commented before a week or two ? Or was that only a feature of the beta boards and is now removed?

No. With the 5v setting it will draw the vdimm from the 5v line. This puts more heat on the vdimm mosfets and around that area, so it needs to be cooled good.

With the 3.3v setting enabled, it would draw the vdimm from the 3.3v line. Max vdimm would be 3.3v but this is 'better' for users 24/7 not running high fsb's and not having to add extra cooling to the vdimm mosfet area.

With OPB using only 2.9v for his GsKill TCCD why use the 5v feature when you can use the 3.3v feature and not put as much 'strain' on the vdimm mosfets.

[mrlobber]

No. With the 5v setting it will draw the vdimm from the 5v line. This puts more heat on the vdimm mosfets and around that area, so it needs to be cooled good.

With the 3.3v setting enabled, it would draw the vdimm from the 3.3v line. Max vdimm would be 3.3v but this is 'better' for users 24/7 not running high fsb's and not having to add extra cooling to the vdimm mosfet area.

With OPB using only 2.9v for his GsKill TCCD why use the 5v feature when you can use the 3.3v feature and not put as much 'strain' on the vdimm mosfets.

I know all the points. But notice what bigtoe said (what I quoted), he has tweaked the pot of the 3.3v line of his Powerstream to 3.6v, to allow 3.5Vdimm. At least that's how I understood the quote. That would indicate, he didn't use the 5vdimm option even though he tested BH-5 and VX, which are the voltage hungry chips. Why? Did the board become too hot even if actively cooled? Was he too busy to mess around with the respective jumpers? Many speculations might be derived... So let's wait what he has to say on that himself

[Tony]

I had stability issues using the 5V setting thats why i went with the 3.3V line tweak to give me upto 3.5V.

[mrlobber]

I had stability issues using the 5V setting thats why i went with the 3.3V line tweak to give me upto 3.5V.

Was that one of the "minor issues" you were talking about in another thread?

[bachus_anonym]

I know all the points. But notice what bigtoe said (what I quoted), he has tweaked the pot of the 3.3v line of his Powerstream to 3.6v, to allow 3.5Vdimm. At least that's how I understood the quote. That would indicate, he didn't use the 5vdimm option even though he tested BH-5 and VX, which are the voltage hungry chips. Why? Did the board become too hot even if actively cooled? Was he too busy to mess around with the respective jumpers? Many speculations might be derived... So let's wait what he has to say on that himself

it's simple as that:
switching to 5V generates a lot of heat on the vdimm mosfets and may cause instabilities if not cooled properly. but if one has no PSU with adjustable rails (be it either modded or factory pots) one needs to use that feature to get more than 3.1-3.2v
on the other hand, if one has the right PSU that gives him enough juice for feeding memory, then just stays with the 3.3v option by cranking up 3.3v rail on the PSU.

[kiwi]

nice
I'd like to see platinum rev 2 sticks