[fwlug] HP's answer to the eee

[Vern Ceder]

Thanks Rob - that is very interesting. And I hadn't heard that they were 
planning a six cell battery for the (wh)eee - that's good news.

All of which goes to suggest (as if we didn't know) that the only way to 
know for sure how a device behaves is test it under appropriate 
conditions. Much as I'm ready for something little and cute, there's no 
way I'm buying even the cheapest machine until I see some reliable 
review/testing info.

Vern

Rob Ludwick wrote:
>> According to the reviews, the optional 6 cell battery gets you 4 hours - 
>> there isn't a larger battery option at all on the eee, so I would count 
>> that as improved battery life...
>>
>> Vern
> 
> I delayed responding to this until tonight when I could find some time
> to finish getting all the details.
> 
> The 6 cell battery for the (wh)eee pc is still "coming soon".  I suspect
> it would probably be out before very much longer.
> 
> Battery life and heat goes hand in hand.  The less heat that you
> generate, the more battery life you get.  Simple power engineering,
> right?  The eee pc uses a celeron M ULV 353.  It requires a fan as it
> gets fairly hot (not on the cpu, but on the chassis).  So it doesn't
> quite reach it's goal of being completely devoid of moving parts.
> 
> Now HP is apparently using a VIA 1.2/1.6 GHz VIA C7-M processor.  
> 
> According to VIA that means it's about 12 watts to 15 watts of power at
> peak.
> http://www.via.com.tw/en/products/processors/c7-m/c7-m.jsp
> 
> The wheee pc uses a Celeron M ULV 343 which uses 5 watts of power.
> http://www.intel.com/pressroom/kits/quickreffam.htm
> 
> But as we all know, it's not the peak power that matters but average
> power.  For instance if you're not using SSE(2) extensions, those could
> actually be powered off inside the CPU.  Also, if there's an idle state,
> the cpu can power itself off until something requests CPU time again.
> 
> On the bottom of the wheee pc there's a sticker that says that the
> adapter must be able to supply 22 watts of power.  So that means 17
> watts of power is split between the screen, the chipset, recharging the
> battery, and the display.  Now the wheee PC gets warm even during idle
> use, this suggests bad power engineering.   
> 
> So where can you save power?  Making sure idle components enter into a
> "low-power" mode.  Using efficient chips for power conversion between
> different voltages.  Using efficient light for the back light, etc.
> 
> So let's dig in a little more.  Look at this picture.
> 
> http://www.tweaktown.com/popImg.php?img=eeepc6_l.jpg
> 
> You can see that the wheee pc's fan sits over what appears to be a
> couple voltage regulators and a couple of coils. Note that when the eee
> pc is put back together the fan sits directly underneath those items.
> I'm guessing those are getting hot.  The fan would not do very much for
> the CPU and chipset, since those are sitting on top of the board, and
> you can see their picture here:
> 
> http://www.tweaktown.com/popImg.php?img=eeepc5_l.jpg
> 
> There also don't seem to be any vents on the keyboard side of the
> chassis.  The only vents are on the underneath with the fan.
> 
> http://www.tweaktown.com/popImg.php?img=eeepc22_l.jpg
> 
> So yeah, I'm guessing that there's no reason the eee pc could not have
> been made to be more power efficient.  They used a pair of bad
> regulators and then had to add a fan when it got too hot.  When people
> tear into the HP, it would be interesting to see if the HP has fans and
> where they are.
> 
> Typically one would expect the CPU and the chipset would be the hottest
> thing running in the chassis, afterall, they're doing most of the
> switching.
> 
> --R
> 
> 
> 
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-- 
This time for sure!
    -Bullwinkle J. Moose
-----------------------------
Vern Ceder, Director of Technology
Canterbury School, 3210 Smith Road, Ft Wayne, IN 46804
vceder at canterburyschool.org; 260-436-0746; FAX: 260-436-5137