ULV vs LV

Hi everyone,

I am on the market for a CPU-centric light laptop and I will definitely need some kind of i7, but the selection of laptops that fit my criteria (powerful CPU, very portable...) is not that impressive. I am generally interested in the speed difference between ULV and full-voltage i7 CPUs and more specifically these two:

i7-3517UE vs i7-3520M

They are both dual core, I know that the 3520M is for sure faster, but by how much? Is the 3517UE comparable to an i5 IVB LV? Some benchmarks seem to show that the i7-3517UE would be comparable to an i7-2640, is that the case? I will be running CPU intensive software, but a 5-10% speed difference shouldn't be a huge problem. I appreciate any comments.

 

Well here's comparison: Compare Intel® Products

3517UE is 17W, 3520M is 35W. There's 800MHz difference at max turbo, which is quite significant at ~ 30% faster clock speed, and has a faster IGP 1.25GHz vs 1GHz. How that translates into real world performance depends on the application.

As an example my 3610qm at 3100MHz vs 2400MHz (similar performance difference) wprime is 8.7 secs vs 11.4 secs ~ 30% faster.

 

Thanks for the link, but I already checked the Intel comparisons and I know that the clock speed difference is substantial. I was wondering how that translates in real life - someone's personal experience or benchmarks. For example according to Passmark the scores are:

i7-3517UE (1.7 Ghz) - 4025 (rank 215)
i7-3520M (2.9 Ghz) - 4540 (rank 182)
i7-2640M (2.8 Ghz) - 4066 (rank 208)
i5-3210M (2.5 Ghz) - 4000 (rank 219)

I am not sure how reliable these scores are, but according to them the performance difference is closer to 10% rather than what the clock speed suggests. Also according to these, the i7 ULV seems to be on par with the full-voltage i7 Sandy Bridge and the newer i5 (both clocked a lot higher). If someone can please give me some personal experience with these or reliable benchmarks that would be awesome.

 

Have you taken a look at the many variants of Clevo W110ER? You're not going to find a better ratio of performance to size (full voltage quad-core i7 in 11.6" chassis) on the market currently.

 

I did look at the Clevo W110ER and while I would prefer a full voltage quad-core i7, I don't really need a powerful GPU like the one in the Clevo (which affects the battery life and the heat levels). My work is 100% CPU based, but I also need portability and good battery life. The laptops that I am considering right now have the listed processors and I think I would be more comfortable with a 13.3" laptop. I was just wondering how much I would lose if I go the ULV route.

FYI I am looking at:

Lenovo x220/x230 - i7-2640M/i7-3520M
ASUS u24e - i7-2640M
ASUS ux32vd - i7-3517UE
Sony S13 - i7-3520M

I really like the ASUS UX32VD, but I am a little concerned about the CPU performance that it offers. If I can get something comparable to the 2640, I think I would be fine. Any opinions on the CPUs would help me a lot.

(I don't want to turn this into a "What Notebook Should I Buy?", I just wanted to give some background to my hardware question)

 

What kind of CPU work are you talking about? What apps? Are there any benchmarks for the apps you're going to be using? Is it compression, video/audio editing, encryption?

Clearly the i7-3520m will crank out more work per hour than UE by like at least 15-20%, that's like 10-12 minutes for every hour of work. Passmark is not a good gauge for performance comparison though. Look at notebookcheck.net and compare the benches between the i7-3520m and the i7-3517U (1.9-2.8GHz 17W) and it should give you a better gauge of performance.

Here's results from notebookcheck.net and remember this is a slightly faster comparison since it's the U and not UE.

3dmark06 ~ 25%
Cinebench R10 Single ~ 18%
Cinebench R10 Multi ~ 13%
Cinebench R11.5 ~ 18%
SuperPI 1M ~ 21%
SuperPI 32M ~ 19%
wPrime 32 ~ 21%
wPrime 1024 ~ 12%
x264 Pass 1 ~ 20%
x264 Pass 2 ~ 16%
WinRAR ~ 15%

Spoiler

 

Thanks HTWingNut, that was very helpful. I just spent some time on notebookcheck.net and saw a few comparisons. It seems that the i7-3517U is a little faster than the SB full-voltage i5-2430M in most benchmarks, but it's a little slower than the IVB full-voltage i5-3210M. So I guess that answers my question - the IVB ULV i7 falls between the IVB LV i5 and SB LV i5, while the LV i7s are 20% faster on average.

With regards to the CPU work that I was talking about - I work with relatively complex statistical/econometric models that take anything between a few hours and sometimes days/weeks (in which case I run them on a server). The software has no GUI and all the work is done by the CPU, basically it uses as much as I throw at it and there are no benchmarks for it as far as I know. Unfortunately, I also travel and I'll need something portable and light at the same time so I can run stuff on the go without killing my back (as I am right now). On top of that, my top priority is built quality (and minimum heat)...So I am not sure what options I have besides the ones I already listed (I will post in the "What Notebook Should I Buy?" section once I do some more preliminary research). If I go with the UX32VD, which seems well made and light, I would have to give up on some of the CPU power. Any opinions and suggestions are welcome.