Post
Topic
Board Hardware
Re: HashFast announces specs for new ASIC: 400GH/s
by
Vbs
on 21/08/2013, 11:17:00 UTC
1) https://hashfast.com/shop/babyjet/ states 350W power draw (+/- 20%), but the chip only consumes 250W?  100W for cooling/misc?

Not sure why this is still a question (goes beyoond just HF).  Remember even excluding water cooling pumps, fans, and controller boards there are a lot of efficiency loss between between the wall and the chip.

"This is still a question" because Vbs is here to spread FUD about HashFast.

He's on ACTM's Board of Cheerleaders, invested more than he can afford to lose, and got married to a competitor's  stock that not only became obsolete soon after launch but is also enduring disasters WRT BTC conversion and bulk Avalon orders.

At this point, asking dumb questions which have already been answered repeatedly is all he can do to prop up his failing stillborn venture.

I'm sorry, who are you again? This kind of ad hominem argumentation is indeed lamentable, so if you have nothing substantial to discuss, please keep to yourself.

I'll reiterate my question about the power figures: Simon, the store page says "* Real silicon power consumption may vary from simulation results by +/- 20%" (I assume this means the chip can be between 200-300W), you would really have no problem if it ever comes to be 300/324 = 0.926W/mm^2? It's still 12% more than an o/c SB-E even at an extreme 350/425 = 0.824W/mm^2.

Using some quick math for forced convection water cooling, with:
Water:  50 - 10.000 (W/m^2K)
Chip area (m^2): 0.000324
t_surface = 80ºC
t_air = 30ºC

q = 10.000*0.000324*(80-30) = 162W, which is a water heat transfer figure under chip requirements, so the heatspreader has to really compensate for the so small chip area!