Something wrong with Intels latest CULV processors (i3/i5/i7-xxxUM)?

I was thinking of buying a new Acer TimelineX laptop, and was considering two models, either an 1830T or a 3820T.

The locally available 1830T has a i3-330UM processor, while the locally available 3820T has a i3-350M processor. I was expecting the i3-330UM to have a much longer battery life.

After reading several reviews, I found a review of the Acer 1830T with with at CNET of a 1830T equipped with a i7-680UM. Battery life on the video playback test was 280 minutes. The same site has a review of the 3820T with the i3-350M processor. Battery life on the video playback test was 260 minutes.

Considering the that i7-680UM is an 18W processor, which the i3-350M has a max TDP of 35W, I expected the i7-680UM to have a much longer battery life.

I also found the test Acer commissioned Principled Technologies to perform to justify the 8 hours battery life claim. The test used was the BAPCo Mobile Mark 2007 test.

Acer 1830T with a i5-520UM (1.06GHz) - 8 hours and 49 minutes
Acer 3820T with a i3-330M (2.13GHz) - 8 hours 9 minutes

It does not seem like the new CULV's (the UM's) provide a significantly better battery life than the standard mobile processors.

 

The 32NM i-series was more for performance improvements than efficiency improvements. 22NM will be efficiency improvements to the i-series though. I think a LOT of people underestimate just how great the Core 2 architecture was. I almost miss it.

 

My i5-450m has an TDP of 25watts according to HWinfo32, it`s 35watts if i use the IPG i think.

 

If you want better overall laptop power efficiency, then the CPU is not where you look.

1) The 18W and 35W are TDP's - Thermal Design Power. They rate the maximum HEAT a chip generates, and ***NOT*** how much POWER they consume.

2) The i7-680UM has a longer battery life than the i3-330M because the "UM" indicates that they are CULV (Consumer ultra-low voltage) processors. They are mobile processors specifically designed to consume low amounts of power and generate less heat (hence the 50% reduction in 35W vs 18W TDP).

3) You cannot compare two different laptop models and assume that the only difference is the processor. There could be differences in software configuration or other hardware components between the 1820T vs 3820T. If that is the case, then those will affect battery life as well. You cannot simply attribute any differences in battery life to just the CPU unless every other aspect about those laptops is identical.

4) The CPU does not consume the most power in a laptop - the LCD screen does. The CPU itself consumes only about 20% - 25% of the power when doing things like idling or browsing the web. Out of an 8-hour run time (480 minutes), 20% of that is the CPU (96 minutes worth of power).

If we assuming that everything else about the laptop is equal, and that the only difference is the CPU, then simply switching from a Core i3-330M CPU to an Core i5/i7-based UM/CULV CPU gets you an extra 40 minutes (42% improvement in CPU efficiency). That is 42% more power efficiency out of the CPU, between two CPU's in the same generation. I don't know about you, but that's pretty darned good to me.

 

The 1830T and 3820T are nearly identical. The main difference is that the 1830T has an 11.6" screen and a 5800 mAh battery, while the 3820T has a 13.3" screen and 6000 mAh battery.

I guess the 40 minutes is okay, but when you consider how much you lose in terms of speed...

 

You are right.

The normal voltage processors can clock so far down, the difference with ULV CPUs has become negligible.

And it's true that the ULV arrandales aren't very power efficient. (just compare 1830t with 1810t, 8 hours vs 6)

If you could get your hands on a Acer 1810t with SU9400 you basically get a better CPU and more battery life.

PS. I do think the 3820T has a bigger battery than the 1830T.

 

The CULV craze never really go off the ground, and the subnotebook fad died with it. Obviously, there are iCore CULV processors out there, such as in the updated HP DM3, but judging by the poor sales in the segment, very few buyers really are interested.

The real problem with the subnotebook concept is that it combined weak processors with even weaker batteries, leading to disappoint battery lives. This is precisely why Acer has moved away from CULVs for the Timeline series, which is supposed to be upmarket, although the product still doesn't seem very convincing.

 

To the above poster who talked about power.

Unless your chip glows or makes a noise all consumed power is lost as heat cussed by the currant flow as the transistors switch.

 

ral,

what you're seeing is the effect of throwing a modern load/task to a modern processor and seeing that the faster processor is the one that does it more efficiently.

The UM series may be more power efficient by themselves (just idling). But that doesn't mean too much in a complete system when they have to do actual (equivalent) work for the same amount of time (lets say to show a full movie).

So, to your question if there is something wrong with CULV processors?

Yes: the price and the performance leaves much to be desired - compared to 'normal' cpu's/platforms currently available - even when battery life is an important criteria.

As to the 40 minutes you lose, this is only if you buy the notebook to leave it on and idling. (In actual use the 'work' battery run times are much closer).

Or, think of it like this: if you are buying to get a certain cpu-intensive job done while mobile, the notebook with the nominally lower run time will finish the job faster. As long as the battery lasts to complete the job you need, you are still further ahead than the CULV option that may take twice as long (or more) to complete the same amount of work.

I think CULV's have long passed their usefulness (ever since Arrandale i3's M's were introduced earlier this year) at least for mobile tasks that put any sort of sustained real demand on the cpu.

 

Put a Core i7-640M in the Acer 1830T and I'd like to hear the fans on that. But really, this is why I am done with ULV processors and my next notebook will befrom the Lenovo X200 series. It manages to combine portability and performance in the ultimate size with great battery life.

 

Thanks for all the replies.

I cannot find details on exactly what voltage a i3/i5/i7 runs. According to Wikipedia both the M and UM chips run at 0.725v-1/4v. Did some more reading, and found this on Engadget:

I guess the 20% battery life saving only gets you so far.

Comparison:

i3-330M runs @ 2.13GHz with a max TDP of 35W
i3-330UM runs @ 1.20GHz with a max TDP of 18W

If you look at the older chips running at the same speeds (more or less)

T7400 runs @ 2.16GHz with a max TDP of 34W
SU7300 (Core 2 Duo) runs @ 1.20GHz with a max TDP of 10W
SU2300 (Core 2 Solo) runs @ 1.20GHz with a max TDP of 10W

 

Don't forget that the TDP of the i-cores also includes the TDP of the memory controller (now integrated into the die) and the TDP of the integrated graphics. This probably accounts for about 10-12W of TDP in and of itself, so you'd need to subtract about that much from the i-core chips.

 

Yea hard... Such an amazing job by intel, they designed the c2d architecture from scratch and finished in 2 years. I loved lga 775 and those c2d chips are still really powerful.

 

Are they so quiet? I heard bad things about Lenovo X300 line.

 

I also looked at all the tests Acer commissioned Principled Technologies (PDF docs posted online) to perform to justify the 8 hours battery life claim. The test used was the BAPCo Mobile Mark 2007 test.

Acer 1830T with a i5-520UM (1.06GHz) - 8 hours and 49 minutes
Acer 3820T with a i3-330M (2.13GHz) - 8 hours 9 minutes
Acer 4820T with a i3-330M (2.13GHz) - 8 hours 35 minutes
Acer 5820T with a i3-330M (2.13GHz) - 8 hours 9 minutes

Hhhmmm... screen size does not appear to be an issue, but these test were conducted at 60 nits.

 

Keep in mind that TDP != power consumption. TDP is a number supplied by manufacturers to let system builders know how much thermal energy a heatsink must be able to dissipate to keep the chip within normal operating temperatures. That's all.

 

and wifi disabled. Battery sizes may be different.

The reason why they get roughly the same scores is that the full voltage CPUs clock down to the level of an ULV CPU.

 

That seems to be the most reasonable explanation. The standard voltage CPU's clock down to the same level as the ULV CPU's.

 

The only reason I see to still buy ULVs is the size of the laptops. In the 11.6" space there are no standard voltage CPUs as far as I know. Acer 1830t, Macbook Air 11.6" and Asus UL20FT all use ULV CPUs.

Probably the smallest standard voltage laptop is the 12" Lenovo X200s.

 

From your comment I gather that you are saying that the only advantage with the ULV is CPU is if the standard voltage ones cannot be installed in 11.6 form factor laptops because of heat issues. Following your lead I used Laptop Mag's comparison chart to compare the temperature of the following units:

Acer 1830T (i5-540UM 1.2GHz)
Heat Touchpad - 88F
Heat G-H keys - 90F
Heat Bottom - 101F

Lenovo X201 (i5-540M 2.53GHz)
Heat Touchpad - 100F
Heat G-H keys - 99F
Heat Bottom - 106F

Asus UL20FT (i3-330UM 1.2GHz)
Heat Touchpad - 88F
Heat G-H keys - 86F
Heat Bottom - 91F (middle)/104F(near vent)

Dell Vostro V13 (SU7300 @ 1.3GHz)
Heat Touchpad - 90F
Heat G-H keys - 92F
Heat Bottom - 100F

 

No, it has more to do with no company has offered 11.6" machines with full power processors yet, the closest we get are 12.1"er's and a 10" Panasonic Toughbook that has full 35W Core i's.

 

After seeing the 99F~106F temps on the Lenovo X201 with the standard voltage mobile processors, I have come to the personal conclusion, that despite the lower performance and insignificant improvement in battery life... the reduction from a max TDP of 35W to 18W might be worth it.

 

Or, simply consider a larger than 12" system with adequate cooling for the much higher performing standard voltage processors.

 

Oh...

Okay, back where I started. Acer 1830T with the 1.2GHz i3-330UM or the "larger than 12" system", Acer 3820T with the 2.26GHz i3-350M.

The new unit is supposed to replace my Asus 1005HA which I got for its light weight (3lbs) and long battery life.

 

The 3820T is definately a great notebook, and very thin for what it is. But if weight is the paramount factor in purchasing, the 1830T is the clear winner.

The i3-330UM scores about 2-300 more CPU passmarks than the T5500 that I have in my older Acer, and it does everything I've ever thrown at it.

 

Just ran Performancetest and had a look at the Passmark database. Cpumarks are as follows. The i5-520M is two times faster than the i5-520UM.

[email protected] = 990 (my system from 2007)
SU9600-1.6 = 1300
i5-520UM = 1455
SL9400-1.86 = 1580
i5-520M = 2800

If going a i-core UM CPU suggest get an i5. Then can use Throttlestop to overclock the turbo boost getting 35% better performance. See http://forum.notebookreview.com/alienware-m11x/524257-how-supercharge-m11x-core-i5-i7-um-cpus.html

 

Lol... no comparison...

33% heavier and about 10x the power/performance.


Get the 3820T.

 

Yes heat, size and power of the cooling system.

Not sure if you know but TDP is not a measure of power consumption. It's the amount of power the cooling system in a computer is required to dissipate.

The reason Acer doesn't offer the standard voltage CPUs in the 1830T, has to do with size, heat, TDP, airflow etc.

Not even twice the power.
1.36kg vs. 1.85kg
1.2GHz vs. 2.26 GHz

What do you do with your computer?

I own the 1830T and it's perfect for normal usage. I wouldn't want to carry the >1.8kg of the 3820t with me. A faster CPU only makes CPU intensive tasks significantly faster.

If you want to make normal usage faster better invest in HDD/SSD.

 

Phil,

I know I exaggerated a little, but I don't think I was too far off (depending on what you want to compare).

I was replying to this:

An Atom powered netbook, if I'm not mistaken?

 

I think he's deciding between Acer 1830T and Acer 3820T so let's focus on that.

The 3820 will be about twice as fast during CPU intensive tasks.

 

Thank you for being polite. I knew it was not exactly voltage but I thought it had a direct relation to power consumption. That is pretty clear for my early posts. It is nice to find a newbie friendly forum.

What do I do with my laptop. Basically, it is a word browser and word processor. I also use it to view picture I take with my digicam. The only game I play is online poker (play money only).

I plan to keep the HP 6510B till it croaks. This is what I use at home. I have a 13.3" Macbook issued by the office, but it is a government issue unit and I am a consultant, not an employee so I do not take it with me. The 1830T, will be for time in between home and office. I do a fair amount of work in the field.

You are right about the use. I am decided on the 1830T. Will try to pick it up tomorrow or before the weekend. 20% heavier with 100% more power does not make sense for my use. 11.6" give me a 100% sized keyboard. Even after a two years on netbooks (S10 and 1005HA), the 90~92% keyboards feel too different from the keyboards on the HP and Apple. I think the 1830T, keyboard is about the same size. I was measuring keyboards on several lappies in the office earlier. 11.2" seems to be standard for the keyboard (minus media keys and numpad, no matter how big the laptop is.

It stings a bit, that it is half as fast with only a small improvement in battery life. But 3-5 hours of normal use is all I really need.

Great forum. Thanks all.

 

On my 1830T with 330um I got about 5:30 with the stock Toshiba 5400rpm drive. When I replaced it with a Kingston V+ I got 6:30.

This is at low brightness, surfing the web with wifi on, measured with Batterybar 3.4.2

 

ral,

just want to confirm your decision. With your stated use the 1830T is definitely the model for you. Congrats! You have taken all the information presented here and distilled them to precisely the factors that are important to you. Good decision.

 

A decimal of a kilo vs more power?

Cmon guys, just take some protein shakes and hit the gym. Then the difference will seem negligible.

 

lol...

nicksti, you have to take into account his intended use too.

 

The difficulty in the choice is not the 11.6" 1830T. A 12" laptop has been the traditional choice for frequent carry. The 3820T is the source of difficulty, at just under 4 lbs, in weight, it could actually be a substitute for a where traditionally a smaller would have been chosen.

 

The 12.1" Asus 1215n may be worth a look too. Granted the dual core N550 isn't as fast as the Core i3 um, but it's fast enough for normal usage. It lasts 5.5 hours on battery and the touchpad is better than Acer's. It's also cheaper.

For the remaining money you could get an SSD which would make it a snappy system.

 

The SSD would most likely add some battery life to the system as well. Just don't get a Kingston V-series. They consume power almost as bad as a hard drive.

 

Thanks all. Pretty much set on the Acer 1830T. Went to pick one up yesterday, but what they had was red and brown. They should have a black one for me in a few days. The one on display had a i3-380UM, though the brochure says i3-330UM. The display unit also had a synaptics touchpad.

The only other thing that caught my eye was a Olympic Edition 1810T. Cost 10% more than the 1830T though.

No 1215N's here. Just the 1201N and the 1215T.

 

Phil,

sorry for being so dumb, but what is the difference between the Synamptics vs. the Alps?

Is one markedly better than another?

I have an Elan PS/2 Port Smart-Pad and it is the best touchpad I have ever used (the apple's are just too, too large).

 

For the 1830T, Synaptics has better gestures support than Alps.

Scrolling on Alps, and especially two finger scrolling is quite bad.

 

I thought I best write a finis to this thread. While waiting for my black Acer 1830T, a client of mine gave me a bonus. A 13.3" Mackbook Air. I am very very grateful, and it is not my carry around unit. While it weighs less than 3 pounds, just about as much as the netbook it replaces... there is still something to be said about the 10.1"~11.6" form factor.

Ironically, after a few days with this thing, I steel feel like picking up the 1830T. But I cannot dispose of this, and cannot justify another laptop

But, this aluminum unit is a great. An 11.6" might have been better... but do not look gift horses in the mouth.

 

I own both the 11.6" Air and 11.6" Acer. Before this I had the new Air 13".

The Apples are much better than the Acer, I think you are going to regret switching to the Acer.

The Acer is a nice laptop but it's basically all plastic, the screen is just ok but not suitable for outside, the touch pad is among the worst I've used. The keyboard is ok but keys are really close together.

The 13" Air has the best screen, even better than 11.6" Air. The aluminum is quite strong and very stiff. The keyboard, touch pad and speakers are in a different league than Acer's.

 

Simply said Synaptics has been making touchpad since pentium 3 laptops, both their software and hardware are good.

 

No am keeping this one. Not that I would ever buy one for myself... but I am keeping this one for a long long long time

And, yes. Apple build quality is excellent.

 

Elantech is good too, I remember being happy with it on my EEE 901. Both are better than Alps.

 

A bonus 'air' from your client is a nice surprise!

For your intended use (surfing, typing, viewing images), you should benefit from a nicer (higher contrast) screen, longer battery life (under OS/x - as long as you don't install flash) and the sturdiness of the Apple build.

Anything more demanding though and the Acer Timeline will be beckoning for a long time to come.

I can also agree with the size difference between ~11 to ~13 inch systems - but if they have the same resolution the slightly larger system is much, much easier on the eyes.

Is this 'air' the newest, or is this the 2007/08 version with the 1280x800 screen and the 64GB SSD?

 

It is the current model 'air' with a 1440 x 900 screen and a 256GB SSD.

 

Nice client bonus.

That must be the current state of the art for battery life, screen resolution, responsiveness and robustness - not to mention lightweight too - for the use you require of it.

I might even suffer with such a system if Outlook (at least) performs as well as it does on my Asus U30Jc Win7x64 8GB RAM system.

Enjoy!

 

My client has commented in the past, that a netbook, well does not really seem appropriate for me when I go into a meeting in suit. I think that is why he got it for me.

Might be too much of a good thing. My two previous carry units were netbooks. My carry units are not treated gingerly. Tossed into a back-pack on trips stuff in between my clothes and files. Hand carried in a PDAIR case or sleeve when I to meetings. The HP 6510B only survived this long because the two netbooks took the beating of being carried around. The Acer 1830T, would have been a nice upgrade to a netbook, without me worrying too much if I accidentally damaged or broke it.

The MBA, is something I really cannot toss around. It's a bit too expensive for that. It is the most expensive laptop, computer or electronic device I have ever owned. The most expensive laptop I ever bought for myself was an Acer Travelmate 6291... everything else has been at least 25% cheaper than that. It just changes how I handle my ultraportable.

It really is impressive. It is so slim it just reaches the USB ports of my 6510B

The slimness is a plus minus thing. I like the 3 pound weight, and nothing can be too light... but I really do not see any point going slimmer than 1". IMHO, slimmer than 1 inch is harder to carry around tucked under your arm..