yeah, there's a jumper to either draw from the 3.3v or 5v rail.
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yeah, there's a jumper to either draw from the 3.3v or 5v rail.
Thats quite simple. The memory controller runs as faster as the CPU does. So a 280x12 2-2-2 will always get more bandwidth than a 280x11 2-2-2.Quote:
Originally Posted by esdee
no it's not that simple! sandra is affected by the multiplier!
a 12 multi should give 300 points more!
Care to Explain a bit more? maybe its just late.. but im a lil lost on how that works..
Quote:
Originally Posted by Dissolved
Maybe you should ask 3dmark2001 about that ;)
Yes it uses the 5V rail for 4V on DIMM.
Actually by using the 3.3V rail you can only get up to 3.2V VDimm which is not adequate i'd say. Setting the jumper to the 5V rail one will get the full 4V. Please note that active cooling on the mosfets is recommended if using the latter.
what i dont understand, is why DFI didnt put active cooling on the mosfets from the factory... im sure they knew it was needed...
To Keep The Cost Lower. They have Sinks on Some Mosfets allready.Quote:
Originally Posted by pik-ard v1.1
what happens if people start RMA'ing them? not only will that dig into that "saved cost", but it will also be bad PR.Quote:
Originally Posted by Dissolved
I suppose that they assume they don't need to be actively cooled. Personaly, I believe that those heatsinks applied don't do anything useful. Not enough spikes and fins to do so.Quote:
Originally Posted by pik-ard v1.1
What makes sense to me is that they don't want to follow up abit's MAX cooling on the mosfets because it was not one of the biggest successes as far as efficiency is concerned.
Quote:
Originally Posted by pik-ard v1.1
Well DFI and Others have Tested the Mobo before they Went Public. So if there was an Overheating Issue, it would have been fixed. Altho BigToe has Warned if you use the 5v line The mosfets will get insanely hot. i think the 5v is Maily for "xtreme" Overclockers.. No one on air Cooling Will need 4v.
Plus, When you phasechange, it also Cools the mobo and all the Componets on it around the CPU..
I used the stock cooler and sent 3.6v to my bh5, cooling the proc. has nothing to do with cooling the ram, you can still go for high memory bandwidth, but even though I doubt I'd add any sinks to the mosfets, I'd probably rather beable to add some nice ones then have some cheap-o crap ones on there from the factory.
I shared that thought... until they died @ 3.6v :'(Quote:
Originally Posted by vapb400
Most other companys thought they would have problems allowing people to use 3Vdimm and above, DFI proved that people are not that dumb and if the memory says only use X voltage, they won't go higher if they can't afford to kill it.
People will be worried about this, but as long as it is set to draw from the 3.3 rail from the factory there really won't be any problems. If it is set to come from the 5V rail by default than there will be problems, people will buy the mobo and drop it into a poorly ventialted case and it will die, but I'm pretty sure DFI knew that and has it set to draw fromt the 3.3 rail by default.
awesome... these dfi nf4 boards are really puttin the smack down.. mines ordered!!! :D
some ocz vx waiting for it
Benny Lodewijk what's the max MemTest stable ? i got 275 2-2-2-5 1T SPi 1 MB 2*512 on DFI Sk754 aprox. 3.6v.
I think I read somewhere that the 5v thing is an all-or-nothing option. You can feed teh vdimm with 5v by adjusting a jumper but it makes things really toasty.
What do you mean all or nothing? You can give up to 3.2V using the "normal" 3.3V rail...Quote:
Originally Posted by zeebs
He means if you set it to 5v the mosfets will be recieving 5v regardless if you use 2.8vdimm or 4.0vdimm
Yep that's true, although there's no need to use the 5V if you're gonna need less than 3.2V... see there's no point ;)Quote:
Originally Posted by kryptobs2000
if you have adjustable rails, you could also raise the 3.3v line up a bit... but not THAT much.
I run my 3.3v rail at 3.9 24/7, would be higher but ovp kicks in at 4.05
is there ANY danger in that, at all? thats an 18% overvolt, which i think would be out of the tolerance of some hardware... but being able to run 3.6V from the 3.3v line (aka, not heating up the mosfets so much), then i would like to be able to do that, since i have winbond UTT chips...
Do we know for sure these DFI boards need a jumper set for the Vdimm to be drawn from the 5V line? From what I read, I was led to believe that 4V is available without any modification whatsoever . . .
yes, they NEED to have one little jumper (or wire... whatever) moved to draw from the 5v line.
You'll get 4v from 3.3v rail without touching the jumper only if your PSU can handle / adjust voltage.Quote:
Originally Posted by matt9669
or
You can switch the jumper to draw vdimm from 5v rail and not worry about the PSU at all.
Although, IIRC I've seen OPB giving only 3.7v using that jumper.