Discussion Forums > Technology
Nvidia DMI chipset development on hold
kureshii:
I was thinking more of a ‘hidden’ HTPC that won't occupy space on the HT rack (although I know many people would rather show off the HTPC on the rack...)
I'm planning on building something like that, with an E5300 + Zotac 9300 (which should definitely be capable of at least 720p playback on CPU alone, and 1080p GPU-accelerated playback). Add in a tiny CompactFlash->SATA adapter with a speedy low-capacity CF card (0.2ms latency, 30MB/s read) and run XBMC Live off it... if my calculations are not in error, a picoPSU 120W should be sufficient to power it all.
And it would fit into a case 17x17x11cm, if I use a Thermalright AXP140+140mm fan for both CPU+system cooling (the heatsink sits in the middle and is large enough to cover almost the whole board :D)
K7IA:
--- Quote --- if my calculations are not in error, a picoPSU 120W should be sufficient to power it all.
--- End quote ---
One objection from here, did you take into account the efficiency of the PSU? most AC-DC converters don't produce the advertised power levels?
and under constant load at +70% output (I mean while watching high def movie) , without a proper heat sink this thing can melt under 10 ampers of current!!!
[edit] ohh, wait this does not look like a conventional copper AC-DC converter. My bad, this is a DC-DC converter, you will need an extra AC-DC converter for this to work :D
from the site!! below the page,
*At max load, forced air ventilation is required. Peak load should not exceed 60 seconds.
kureshii:
The picoPSU is at least 90% efficient (which shouldn’t need to be factored in since its max output is 140W, although it is rated for only 120W). It also helps that it’s DC-DC only. Even with a power brick, it breaks the 80% overall efficiency mark.
The current family desktop (E5300 + G41) hardly even breaks 80W playing 1080p files, so that’s roughly what I would expect from this combination. Benchmarks seem to agree; some numbers from Anandtech:
Idle power consumption: 67.8W (http://www.anandtech.com/mb/showdoc.aspx?i=3432&p=11)
H.264/Bluray playback: 83.3W (http://www.anandtech.com/mb/showdoc.aspx?i=3432&p=7)
Keep in mind that Anandtech’s test rig was running on a Q9300 quad-core + 1 platter-based HDD and 2 optical drives, so numbers with a Pentium E5300 should be at least 20W less at load, maybe 5-10W less at idle; I can’t find enough sensible power consumption numbers for E5300. The HTPC will also only be running 1 CompactFlash-SATA drive, and no optical drives.
The Atom-flavoured ION board only consumes 30W on load (Atom+9400), and I doubt a Pentium would eat 70W of power by itself xD Besides, the CPU isn’t even going to be that taxed, thanks to GPU offloading.
Numbers from TechReport seem to agree:
Idle: 60W, Load: 96.1W (http://techreport.com/articles.x/15690/12)
Again, note that TechReport’s load profile consists of a multithreaded render that is highly CPU-taxing — I doubt any of the 1080p files in my collection will push the processor that much, especially with GPU off-loading. Remember that this thing is only going to run XBMC Live (with a slim Linux build)
A 120W AC-DC converter is usually available from the same places that sell the picoPSU :)
K7IA:
^ O.K now I am jealous.
One last thing,
It says HD movie tests but the source is BluRay (Mpeg2 and H.264?) which I think requires a lot less processing power (lower cpu/gpu utilization) compared to the immensely compressed and high encoding profile High-Def animations and movies we usually download.
I think the nominal power consumption would be between a BluRay HD movie power consumption (83w) and gaming power consumption (110 watts) and they are using a Corsair HX520 as Power supply which produces 520W. http://www.corsair.com/products/hx/default.aspx
Which is more important. Because the Corsair psu produces 140W of total power on +3.3V and +5V while picopsu outputs 19w and 30w of power on +3.3v and +5v respectively. Now if the CPU is consuming 3.3v channel, and Intel E5300 is rated at 65W , expect a brown out reset :(
kureshii:
--- Quote from: enginarc on October 14, 2009, 07:10:22 AM ---Which is more important. Because the Corsair psu produces 140W of total power on +3.3V and +5V while picopsu outputs 19w and 30w of power on +3.3v and +5v respectively. Now if the CPU is consuming 3.3v channel, and Intel E5300 is rated at 65W , expect a brown out reset :(
--- End quote ---
I should hope a Pentium E5300 won’t draw enough power to cause a brown-out :\ I read many success stories with Athlon X2s on HTPCs, and it would be hard to believe that an E5300 manufactured on a 45nm-process would kill a 120W picoPSU where the 65nm Athlon X2s failed to do so.
SPCR was kind enough to do a power distribution measurement test. The results are 4 years old and hence should be carefully analysed with the right assumptions, but I would be very disappointed if the Pentium E5300 ends up pulling more current on the 3.3V and 5V lines than a Northwood P4 (LOL!)
IIRC from most of the articles I've been reading, on most systems built in the past 4 years or so, most of the power draw would be on the 12V rail. This is a result of the ever-increasing power draw of computer systems (you get less wire resistance at higher voltages), as well as a greater awareness of power efficiency and a push toward greater power efficiency (c.f. the 80 PLUS Program, and the 80 Plus Certification for PSUs), and is also reflected in the current-limit distribution of PSUs (Just compare the maximum current load per rail of a 5-year-old PSU, to that of a modern PSU).
In the worst-case scenario I guess I'll just have to plonk more money down and go for a 150W picoPSU :P
[edit]Found some cheesecake!
That's a Scythe Big Shuriken HSF sitting on top of the CPU; it is slightly off-center, but cheaper and shorter than the Thermalright AXP-140 (pictured below):
Free GPU heatsink + memory ventilation as well, and 120mm-fan silence to boot.
With the Scythe, the overall system height works out to be about 8cm =D
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version