Most Power Efficient CPU?

[sthayashi]

I was thinking about this for some time and it's occurred to me why exactly underclocked computers scare me (and possibly others) as well as the Via machines. I keep this sense of paranoia that usability will suck, because it's hard to appreciate how much we need out of a computer.

So what I propose is this. We don't need specific benchmarks for the underclocked computers. What we need is a series of validations tests, or a series of regression tests, if you prefer.

This would include things like:

• Time To Boot
• Time to start IE
• Time to start Adobe Acrobat Reader
• Can it play a 128 kbps mp3? 320kbps? (y/n)
• Can it play an mp3 while browsing online? (y/n)
• Can it play a DVD w/ 5.1 sound smoothly (y/n)
• Can it play a DVD resolution Mpeg-4 w/ 5.1 sound smoothly (y/n)
• Can it do Quake III @ 60 fps? 85fps?

Does anyone have any comments or suggested additions to this list? I figure that this accounts for 90% of my time on a PC and I suspect that it would account for most people's time on a PC.

[silvervarg]

So what I propose is this. We don't need specific benchmarks for the underclocked computers. What we need is a series of validations tests, or a series of regression tests, if you prefer.

This does sound reasonable. But there is a few things that comes into play here. Gaming and DVD playback is heavilly depending on both floating point calculations and the speed of your graphics card.

I run an underclocked XP2500+ to XP1500+ speed passively cooled, so I will do my best to answer your questions.

Time to boot is faster than a stock XP2500+. Ok, this really sounds too good to be true, so lets explain why. First of all I have higher FSB and lower multiplier, so memory and HDD speed is really faster than a stock XP2500+. Secondly I have stripped off excessive hardware, and this saves some time during boot. I normally run without floppy and without optical drive. In adition to this I did some tweaking in the OS and removed all crap at bootup, so in total this machine boots a lot faster at XP1500+ speed than my Intel 3.0 machine at work does.
The conslusion is that the CPU speed is not very important for boot speed, but FSB makes a little bit of difference.
In addition to this I run my machine 24/7, so I seldom reboot.

Starting a program is mostly disc-bound, and slightly memory bound, so CPU speed is not very important here. This goes for both starting IE and starting Acrobat reader. If you really want exceptional disc speed you should get an IDE flash drive (the 800MB ones are really cheap). This will probably make your programs start at least 5 times faster.

Can I play mp3 at high rate and browse at the same time? No problems at all. This uses very little CPU, so I guess even the VIA C3 will do quite fine here.

Can I play DVD's smoothly? Yes, but I typically don't do it on this machine with only integrated video on motherboard (Abit NF7-M). I don't have a 5.1 system connected, so I have not tried that.
The truth is that when I want to play games and play DVD's the speakers will make so much sound that I can tolerate the machine to make a little sound. So, I change change vcore, multiplier and FSB to clock the machine up to over XP2500+ levels. Maybe it is just vanity, but getting a few extra fps is always nice.

There is a major difference here with underclocked machine and a machine that is slow from the start. With a slow machine you can not increase speed when you need to. The VIA C3 is not made for gaming. If you are a gaming freak you should have one gaming rig and a VIA rig for more normal stuff. DVD playback is border-line for the VIA CPU. With a graphics card that does most of the work you can get great playback.

[pod03]

My experience agrees with silvervarg.

I have never had a crash when adjusting the FSB with 8rdavcore with the limits that I use 60MHz and 133MHz (5x Multiplier so 300MHz to 665 MHz). I always use autoFSB to reduce FSB, but always drag up the FSB with the slider when increasing FSB as with the settings I tried it is quicker to do this than wait for 8rdavcore to do it. Never a need to reboot. A FSB of 200MHz or more may be possible with the right setup (memory, voltages etc).

I do need to reboot if I want to change the multiplier in BIOS. If something does not work at the max FSB that your system is stable, you would just have to have a compromise between minimum and maximum processor speed. With an XP-M you may be able to change the multiplier in windows with CPUid or SpeedSwitch see http://forums.silentpcreview.com/viewto ... highlight=

Mark

[sthayashi]

Well, I'm glad that both of you have had roughly the same experience. I do want to clarify some things.

First, I mentioned Adobe Acrobat Reader specifically, because it seems that no matter how fast a machine I'm on, it always takes forever to load and I wasn't sure if it was disk limited (since I've copied several hundred megabyte files in shorter time than it takes to load).

Second, I wasn't aware that video cards had any impact on DVD or DivX playback. In fact, I thought that was why Via specifically included Mpeg-2 decoder hardware on their Eden platform. So that it could play DVDs. The reason I bring this all up is because IIRC, it was between the 300-800MHz range where Mpeg-2 and Mpeg-4 playback was not trivial. And when Sigma Designs brought out their Mpeg-4 hardware decoder, it made news.

But I think everything I need to know has been answered. I really only have two goals. 1) To have a much quieter machine than what I'm currently using and 2) To have it low powered enough that I don't feel bad about wasting electricity if I left it on 24-7. A third underlying goal is that it can perform adequately for my day-to-day needs. I think I have enough information now for all three.

Thanks everyone.

[Blappo]

First, I mentioned Adobe Acrobat Reader specifically, because it seems that no matter how fast a machine I'm on, it always takes forever to load and I wasn't sure if it was disk limited (since I've copied several hundred megabyte files in shorter time than it takes to load).

To speed up the loading of Adobe Acrobat Reader move everything in the "plug_ins" directory to the "optional" directory except for: eBook.api, EWH32.api, Search.api

Before I learned this trick I stuck with using version 5 since version 6 takes forever and a day to load.

[silvervarg]

Good to hear that this was enough answers for you.
The questions you brought up was very good, so I think it is good to dig slightly deeper to get all the answers.

I am no expert on DVD and DivX playback, but if I remeber correctly DivX uses more CPU power. It also makes a lot of difference what player you are using and if you can use hardware features of offload the CPU.
Perhaps someone with a CPU clocked down to ~500MHz can try this out and give some real answers on how it works. Tests with VIA C3 of different speeds would also be welcomed.

As for Acrobat reader, could you give an estimate of how many seconds "forever" is? I would say it takes 5 seconds top on my machine to load version 6 (with a rather small PDF-file).

I have had some thought on a completely silent box, powered either with the VIA C3 or the Geode NX1500. So more info on how these CPU's handle movies is appreciated. I have seen ads for VIA C3 boards with TV-out and only 600MHz VIA C3. This sounds a bit on the slow side for movies. Has anyone here tested this?
Does it work fine view a movie file over the network? How much bandwidth does a DVD need? Does it add a lot to the CPU load?
This becomes a very important question for a no-moving-parts-computer, since there is no reasonable way to store the movie local on that computer.

[msde]

I just wanted to point out a related topic of interest done by google. Google is interest in minimizing search per query. This means buying the most powerful, cheapest hardware possible that consumes the least amount of power. If there is a way to track down their findings, it might be similar enough to help.

http://www.manageability.org/blog/stuff ... cture/view

[dasman]

To speed up the loading of Adobe Acrobat Reader move everything in the "plug_ins" directory to the "optional" directory except for: eBook.api, EWH32.api, Search.api

GREAT TIP!!!


Dave

[stmok]

Good to hear that this was enough answers for you.
The questions you brought up was very good, so I think it is good to dig slightly deeper to get all the answers.

I am no expert on DVD and DivX playback, but if I remeber correctly DivX uses more CPU power. It also makes a lot of difference what player you are using and if you can use hardware features of offload the CPU.
Perhaps someone with a CPU clocked down to ~500MHz can try this out and give some real answers on how it works. Tests with VIA C3 of different speeds would also be welcomed.

As for Acrobat reader, could you give an estimate of how many seconds "forever" is? I would say it takes 5 seconds top on my machine to load version 6 (with a rather small PDF-file).

I have had some thought on a completely silent box, powered either with the VIA C3 or the Geode NX1500. So more info on how these CPU's handle movies is appreciated. I have seen ads for VIA C3 boards with TV-out and only 600MHz VIA C3. This sounds a bit on the slow side for movies. Has anyone here tested this?
Does it work fine view a movie file over the network? How much bandwidth does a DVD need? Does it add a lot to the CPU load?
This becomes a very important question for a no-moving-parts-computer, since there is no reasonable way to store the movie local on that computer.

Forget VIA C3 at 500Mhz...Its too slow for video playback.

This is what I did instead of buying a C3.

PowerLeap PL-iP3/T ver 2.0 slocket using the following...

Celeron 1.2Ghz (Tualatin, S-Code: SL6C8, tB1 core stepping)
Default setting
Speed = 1200Mhz (12x 100Mhz)
Default voltage = 1.5volts
Max Power Dissipation = 32.1W

Underclocked mode
Speed = 800Mhz (12x 66Mhz)
Core voltage = 1.025volts
Max Power Dissipation (estimated) = 9.9W (68.8% drop)

Cool as a VIA C3 1Ghz chip...But FASTER!

There are Mini-ITX mobos for Socket 370 (using i815 chipset).

[ipaqgeek]

To speed up the loading of Adobe Acrobat Reader move everything in the "plug_ins" directory to the "optional" directory except for: eBook.api, EWH32.api, Search.api

I love little easter eggs like this. thanks!

Cool as a VIA C3 1Ghz chip...But FASTER!

But your Celeron doesn't have hardware MPEG-2 decoding, so it depends on what you're doing. For most apps the Celeron is faster though.

I switched from Epia to an Underclocked AMD XP M because I do flash animation, and that's mostly CPU related, but for MPEG-2 movies embedded in flash the Epia does better.

[Linus]

Similar thread here: Lowest power consumption for DivX encoding.

[sthayashi]

I should follow up on this, even though I'm sure I've posted this elsewhere.

I ended up getting an Athlon XP-M 2600+ & an Aopen AK79D-400VN. I boot it at 1.35v & 2GHz. After bootup, I use 8rdavcore to reduce the Vcore and clock to 1.1v & 1.2GHz. It runs rock solid at this level and is plenty fast enough for everything I do, except audio encoding. Whenever I need to encode audio, I crank it back up to the boot speeds, and it's fast enough for me.

For the record, I ripped a CD to MPC a few days ago at both speeds. At 1.2 GHz, it encoded at 10x speed. At 2.0 Ghz, it encoded at 20x speed (Note: Musepack is a pretty fast codec to begin with, so this may not be as impressive as it seems).

At the 1.1v setup, it draws 48-49W AC at idle. Since this is less than the power of the average incandescent lightbulb, I'm pretty comfortable leaving it on all the time, and it is by far the quietest machine I've assembled. It's only audible when everything else is silent and if I try to do any more work on it, my wife is going to have me committed to an asylum.

[burcakb]

You might also want to switch to CrystalCPUID. You can set min, medium, max settings and it'll swithc multiplier & Vcore instantly based on processor load (you set that too). Much like Cool & Quiet except you configure it according to your own load and it's automatic

I've found that my Athlon 3000+ will stay at 1100 MHz & 0.9V for almost anything (including divx playback) except gaming and folding.

[sthayashi]

You might also want to switch to CrystalCPUID. You can set min, medium, max settings and it'll swithc multiplier & Vcore instantly based on processor load (you set that too). Much like Cool & Quiet except you configure it according to your own load and it's automatic

I've found that my Athlon 3000+ will stay at 1100 MHz & 0.9V for almost anything (including divx playback) except gaming and folding.

I gave CrystalCPUID a try. I really did. But the first version I downloaded didn't even work with my setup. When I actually got one that worked, the dynamic switching crashed my system. I'm a bit reluctant at this point to try it again until it works better. I don't think I can take my system much lower than it currently is.

[HammerSandwich]

...it is by far the quietest machine I've assembled. It's only audible when everything else is silent and if I try to do any more work on it, my wife is going to have me committed to an asylum.

I can vouch that it's exceptionally quiet - one of those machines that's slightly audible but not annoying even late at night. BTW, you should update your sig.

And I'm sure she'd have NO problem with that.