T420 i5 or i7?

[wkearney99]

Does the T420 get similar battery life out of both processors when NOT performing high load tasks?

As in, should I just spring the extra money for the i7?

I'm looking at an i5-2540 but wonder if it's worth shelling out a little more to get the better processor. But I don't know whether the i7 will generate more heat and consume more power under regular use. Like web surfing over wifi and the like. On the relatively infrequent occasions when I'll be doing some video editing, virtual machine tests or software development it might be handy to have the added abilities of the i7 CPU. But not if it means the unit gets a lot hotter and gets worse battery performance day-to-day.

So I'm about to pull the trigger, i5 or i7?

[Q-Ball]

i5-2520M. Spend/save the rest of that cash for an SSD- that'll make that computer seem way faster than a simple processor bump. It will give faster booting for the VM's, and faster loading of programs. Your computer will be ready for use 20 seconds after you hit the button.

If you don't want to give up the hard drive, just get a mSATA SSD instead- the 80 GB model costs $190 if you install it yourself. You will have to re-install Windows onto that SSD to have it as your boot drive- legal ISO's of Windows 7 are available (search this forum for details)- or you can just create recovery disks, take out the main drive, and use them, which will install Lenovo's drivers in one shot as well.

By the way- it does get similar battery life, the i7 doesn't get any hotter than the i5, and it's not worth the extra 50/100 bucks to go to a faster processor since it's not like the i7 has any features that the i5 doesn't.

[ThinkRob]

My advice would be to save even more money and go with the i3. I really doubt you'll notice a performance difference, and the extra $50 could go towards a bigger SSD or some more RAM.

Or towards a budgie. Budgies are cool.

[blackomegax]

Except the i3 lacks features and does not come with the option for Nvidia GPU.
If you dont need the gpu and the missing features, the i3 has considerable savings, but is also considerably slower than the i5, which is pretty much as fast as the i7 thanks to turbo, and even without is within a margin of it.

[ThinkRob]

Except the i3 lacks features and does not come with the option for Nvidia GPU.

It lacks AES-NI and "Turbo Boost", neither of which are terribly useful for the average user. Turbo Boost is great if you have a heavy, bursty, single-threaded workload. AES-NI is useful for anyone using encryption code that takes advantage of it -- but AES is *fast* in software, and even an i3 will be able to handle the load of, say, full-disk encryption without breaking a sweat.

but is also considerably slower than the i5

It's slower, sure. Considerably? Not so much. Most users really simply won't notice. Heck, I do software development all day on mine and I don't really find the i3 lacking. I put the $50 I saved towards a new Intel SSD which absolutely *did* produce a noticeable improvement.

[wkearney99]

i5-2520M. Spend/save the rest of that cash for an SSD- that'll make that computer seem way faster than a simple processor bump. It will give faster booting for the VM's, and faster loading of programs. Your computer will be ready for use 20 seconds after you hit the button.

If you don't want to give up the hard drive, just get a mSATA SSD instead- the 80 GB model costs $190 if you install it yourself. You will have to re-install Windows onto that SSD to have it as your boot drive- legal ISO's of Windows 7 are available (search this forum for details)- or you can just create recovery disks, take out the main drive, and use them, which will install Lenovo's drivers in one shot as well.

By the way- it does get similar battery life, the i7 doesn't get any hotter than the i5, and it's not worth the extra 50/100 bucks to go to a faster processor since it's not like the i7 has any features that the i5 doesn't.

I went with the i7. The price difference wasn't enough to bug me. Since it'll deliver more or less the same battery life it's a wash, for me anyway. I'd much rather have it than not, but not if it crucified battery life. So we'll see how it goes.

My plan is to add an mSATA, which one's the best price/performance/battery deal? It also included a free drive upgrade from 320 to 500. It'll make using the 500 perfect as a data drive for the mSATA boot.

I'll also another 4gb DIMM to bring it to 8gb. They were offering a free upgrade from 2gb to 4gb as one DIMM, so that saves me from chucking a 2gb and having to buy two 4gb (for a lot less than the outrageous price Lenovo would gouge).

I have a Technet subscription so obtaining legit ISO images and keys is not a problem. I've tangled with recovering and /or reinstalling laptops before, so I plan on having plenty of time free for the ordeal.

Then it's a matter of finding the best price on a docking station, bag, sleeve and another power supply (1ea office via dock, bag, boat).

[Vempele]

Turbo Boost is great if you have a heavy, bursty, single-threaded workload.

Doesn't have to be bursty or single-threaded (the i5-2520M can go 1x3.2GHz or 2x3.0GHz):

Funny thing, also, "lenovo turbo boost+" setting in power manager makes purchasing anything but the lowest turbo capable i5 moot and wasteful (short of the i7 cache boost), as it basically allows it to run overclocked to 3 or 3.2 as long as it needs to.

http://forum.thinkpads.com/viewtopic.php?f=45&t=96198

[antskip]

wkearney99: I have a similar choice with the T520 - for the same price one can choose between a dual-core i7-2620M and a quad-core i7-2630QM. The other constraint is that only the quad is bundled with 2 gpu's under optimus. The 2620M only has the Intel. Despite benchmarks and reviews it is so hard to know really how different such choices would be in reality... e.g. speed, heat, sound...

[ThinkRob]

Doesn't have to be bursty or single-threaded (the i5-2520M can go 1x3.2GHz or 2x3.0GHz)

Well the greatest benefit is from single-threaded. Still, you're right in that it can clock up on 2 cores. It is "bursty" though, as it will only clock up if it can stay within a certain thermal envelope -- and at the highest clocks and when running in a notebook it can't do that indefinitely...

[simplify]

It's slower, sure. Considerably? Not so much. Most users really simply won't notice. Heck, I do software development all day on mine and I don't really find the i3 lacking. I put the $50 I saved towards a new Intel SSD which absolutely *did* produce a noticeable improvement.

I'm easily irritated by slow response (opening/closing apps, web browsing.... I've given up all hope on quick startups), probably a lot more than most people. Of course it's hard to say what exactly 'slow' means, but does this mean I'd be better of with an i5?

I'll have to hold out on SSD until the prices drop.

Also, what is a 'heavy, bursty single-threaded workload"?

My heaviest use would be to have these all open at the same time:

- 3 Word docs, 2 Excel spreadsheets, 3 pdfs
- Netlfix movie streaming, or internet radio or iTunes
- Firefox with 8 or 10 tabs open
- maybe ArcGIS (mapping software; not remotely as resource-intensive as CAD), in which case I wouldn't expect streaming media to run smoothly

[ThinkRob]

If you're after fast response times, an SSD will do you far, far more good than an i5.

[antskip]

I agree. Replacing a HDD with a SSD will do wonders to any system. As long as it has enough ram also, most activities should be almost instant - and quiet. You will never want to use a HDD as a system drive again...