Dell XPS 15: core i5 vs core i7

Hi Guys,

I am a newbie to the forum (but certainly not a newbie to the world of notebooks )

I am thinking of ordering the Dell XPS 15 and am really confused by Dell's options for core i5 and core i7.

-RANT-I am very well aware that the quad core i7 (Dell offers atleast) doesn't have an Integrated GPU to take advantage of Optimus. I don't know for what reason then did Dell opt to go for the medium class GT435M card (which is supposed to support Optimus) in conjunction with the i7. They could have chosen a higher performing card from ATI/NVIDIA. Atleast they could have offered the GT435M with the core i5 but Dell shows a compatibility error and allows only the lowly GT420M even though 435M is supposed to work just fine. I don't buy into the 2GB VRAM as I am aware its just a marketing hype.-RANT-

Now, I am a hardcore media enthusiast. I rarely play games on my laptop as I have a Playstation 3. I work with photography and watch HD movies a lot and maybe a lot of BluRay's in the future. I don't use high level stuff like AutoCAD, Maya etc. but use Adobe Photoshop regularly and DVD/Blu Ray decoding for playback occasionally.

Considering Dell's stupid options and the fact that I need a laptop now:

1) Would it be better to opt for the Core i5 + NVIDIA GT420M and Optimus? Is Core i5 good enough for Blu Ray playback and Photoshop without any glitches?

2) Is it true that the Core i7 generates a lot of heat due to its 45 Watt power rating? I am afraid if I go with the i7 I might not get a lot of advantages, generate more heat and ultimately damage my laptop.

Any input is appreciated guys! Thanks a bunch!

 

Yes, the i7 runs hotter. No, of course it wouldn't damage your system!

If a laptop is well designed the heat generated by the components should never be a problem. It takes a lot of heat to hurt them, and in most cases they have failsafe measures that kick into effect to protect them in case it really does get that hot-- the computer will NOT let you damage it, so fear not.

Furthermore, the only time heat should be an issue is if you're noticing it. If the laptop is poorly designed and your work area is uncomfortable, that is a huge problem. You can say that heat is more of an issue for you than it is for the computer. But this has nothing to do with the CPU used-- just the design of the computer itself.

 

The only people who should be worried about differences between i3/i5/i7 are gamers or people who design 3D animation, because those involve non-stop calculations and 3D motion pictures. An i3 is sufficient for anything else as long as you use it wisely, meaning not opening like 100 Firefox tabs or 10 movies at once. This entire thing is only for psychological reassurance that you have "better specs" than other people, but most of the time does it really make a difference in performance? No. Perhaps you might notice a 0.00001 second speed difference, but that's not really detectable by humans.
So if you don't play games and don't design 3D animation, then an i3 with any graphics card is more than good enough. If I were you I'd go with a laptop with a stylish design and long battery life (unfortunately other than MacBooks, such laptop doesn't really exist).

 

Thanks guys! I agree with Heartcloud that Dell's design for the current XPS sucks. Unfortunately, right now only Dell, ASUS and MSI have the right blend of specs and features I need. Eg. 1080p screen, good speakers, USB 3.0, bluray drive, NVIDIA Optimus etc.

And I am not a big fan of ASUS or MSI's designs compared to this. I also considered the HP Envy but I had a friend who had horror stories with it after it broke down and customer support claiming parts were not in stock etc (Radiance Display mostly). From my past experience, Dell's customer service is a little better.

Since the video card is more important, is the GT435M really better than the GT420M? I checked several websites but I see no clear advantages. Any thoughts?

Based on your inputs, I am inclining towards the core i5 option as of now.

 

Like I said if you don't play games even Intel HD graphics would be sufficient for you. You shouldn't worry about graphics card on a laptop, and often graphics card as well as stylish design are the hardest criteria to meet when searching for laptops, and closes a ton of doors. I've been looking for a stylish laptop with a 5650-level graphics card for weeks, and dead ends just keep coming (like the discontinuation of SXPS 16), I've given up now and will just wait until Christmas for the sales or new models.
If you plan to play games on low settings, then GT420 is sufficient. GT420 is roughly the same level as ATI 5650, which is the entry level graphics card for laptops that are suited for gaming. Anything below that you will experience slight lag for demanding games like Starcraft II or Mafia II, but still ok for most other games on lowest settings (like ATI 5470 or GT310). GT435 is better than 420 and lets you play most games on medium settings with no lag, it's roughly the same level as ATI 5730, and some games on high settings. But Dell's dumb design or marketing strategy forces you to buy an i7 for the GT435, which in my opinion is not worth it.
Stick with Intel HD integrated if you won't game that much, or GT420/ATI 5650 if you play games a lot, or go all out (at the cost of battery life and heat) and get that 5730/GT435 if you really care about graphics quality.

 

I don't see much reason to get the i7. It seems to me more like megapixels on a camera. It's a marketing thing for people who are automatically drawn to "bigger and better", but unless you actually need to make poster-sized images, you don't that many megapixels. Same goes for the processor. Unless you are using very demanding specialized software, the i7 is probably not necessary. For me, battery life and temperature are important and a core i5 will be better in both of those respects.

 

Like I said, I really don't know why Dell is doing this. They should have bundled the 435M with the i5 for the perfect blend in my opinion. I saw this review for NVIDIA Optimus at PC Perspective - http://www.pcper.com/article.php?aid=868 and was sold on the technology to conserve battery. Thanks for the advise on the level of the cards though. I think I am going to go for the GT420 as I dont think any other brand has something solid planned as of now for the holidays. I would have gone for the Macbook Pro but I want more bang for the buck. I don't want to have dead weight slab of aluminum 2 years later because of Apple's paltry hardware offering.

You are right on that one Ichinenjuu. After clock speeds were limited by physics, Intel had to rely on another marketing strategy to keep selling processors and thereby the multiple core processor hype started I guess.

 

Not at all. I have an i7 and wouldn't have it any other way. I frequently tab between games, music players and internet browsers at the same time-- a load that would seem relatively sluggish on a dual core screams on a quad core: I've experienced this first hand.

Of course, if I didn't multitask so heavily, it wouldn't be worth it.

Kinda shortsighted to say that it's pointless just because it's useless to you. In my opinion, the only reason to get a dual core, really, is battery life. Like I've explained before, heat is a non-issue in all but the smallest of systems.

 

Thanks for that input! I am just thinking Optimus will be the best option for me since a decent battery life + less heat is what I want for my laptop. But, isn't it true that clock speeds on quad cores are limited due to heat concerns. So theoretically, for many daily usage tasks sometimes a higher clocked dual core processor might beat the quad core right? I read about this some time ago on Tom's Hardware guide (I am sorry I am not a processor expert! I am just seeking opinions.)

 

In some cases, yes, on paper. But not enough that you'd notice-- maybe a split second? This difference is going to diminish rapidly as time goes on, and soon enough it's going to be the other way around. The only reason it is so right now is because quad cores are relatively new to mainstream consumer systems. Already there are applications that benefit more from one extra core and not at all or very little for increased clock speed.

See here:

Medal of Honor Single Player Graphics & CPU Performance > CPU Scaling - Core i7 9xx - TechSpot

They increase clock frequency by 100%, but performance only goes up by 9%. This is an application that is able to fully utilize four cores. Eventually optimization like this will trickle down to everything.

This isn't to say that you shouldn't go for the dual core, though. This is a laptop after all, and if you need the battery life, well there's no helping it.

 

Agree with all. A year ago, I bought i7-720QM with a laptop, same as everyone else who buys i7 quad - we thought it would be better than what we had, and super powerful. We were wrong. Unless you're one of the rarer few that relies heavily on 4 cores, then it is pointless to buy this furnace of a slow CPU.

So what they are doing with the XPS (as they did with the SXPS 16) is try to push a lot of i7 quads out. Which I really don't understand. Yes, i7 quad is more expensive, but it is also heavily discounted when compared to i5. They are acting as if i5 is gold and i7 quad is bronze. If I wanted to buy i5-520M I end up paying much more than for i7-740QM. It's bloody stupid.

That they do not allow GT 435M with i5 is a mean trick. For this reason alone a lot of us have not purchased the XPS 15. Not to mention Dell reps have lied to me about this issue. And I am not biased against Dell - Dell is the first brand I would consider - and I own 3 Dell PCs.

 

Totally agree poiuytre. Ideally the i7 is suited to a moblie work station as the heat it produces needs a decent sized chasis to dissipate properly.
Also the battery life will be dismal.

I bought the xps 15 yesterday with i7 and 435m as Dell put a stupid offer on the UK website which made it half the price of an i5 model with similar specs!

I know it is going to run hot and battery life will prob be 1:30 but I really wanted the 435m and decent speakers so I can put up with the lack of mobility.
I will get a tablet for mobility and keep this laptop to a desk

 

Yes, if I had a deal that made it much cheaper than it is now, I would totally order it - because I need a laptop right now, I like Dell, and I know if the i7 causes any related problems Dell has no choice but to fix it.

 

i7 Quad-core advantages:
4 cores- Multimedia applications often support (and run better with) multiple cores. The SXPS 16 was sold as a multimedia laptop (not sure to what degree this applies to the new XPS series), but that's the true userbase for the SXPS 16. It's certainly not gamers. The i7 quad will slay the i5 in tasks like video editing.

Faster Memory (30%), Better memory controller (on-die), Faster Bus (30%), more L2 Cache (double)- chances are you would experience the difference if you had an i7 and i5 laptop side-by-side and used both frequently. The i7 will be a drop "snappier" here and there.

It's usually cheaper- This is a biggie. Intel puts a higher price tag on ALL the quads. For whatever reason, Dell, in the past for the SXPS 16, makes the i7 quads cheaper than the i5's, and not just a little bit. In some cases it would cost you $200+ just to get a WORSE processor (in Intel's mind).

Comes with a better GPU- The Nvidia 435M. I don't know much about this GPU except that it has better performance than the 420M by a significant amount. The 420M is quite a bit worse than the cards used in the old SXPS 16 (the ATI 4670)

i5 Dual-core advantages:
Better battery life- The i5 uses less power overall than the i7, but this may only affect battery life by 10% or so if doing simple tasks like web browsing. The OPTIMUS will likely double the battery life (up to the 9 hour range) when doing simple tasks like web-browsing.

Less power/heat- The computer doesn't give a damn how hot it gets, but you might! It may be a few degrees cooler here and there.

Faster clock speeds- It is possible that certain single and dual core applications may actually run faster with the i5. It's hard to say, maybe if you were going to run a single-threaded application to discover digits of pi the i5 is probably marginally faster. But for everyday applications it really won't matter.

 

I did exactly the same - i7 with 435M worked out at basically £700, undercutting everything else in its class by at least £250.

Had it been usefully cheaper I would've had the i5, but the price worked out about £40 cheaper, and with the 420M instead of the 435M. The i7 was a bit of a no-brainer really despite being more than I really need.

 

I think he's talking about the £496 deal that was on for about 30 mins yesterday...

 

Yep, thats the one! absolute winner
Just hope Dell honours it, but I have had a comfimation through so looking good so far

 

I also went for the uk offer but cancelled it later because I had buyers remorse about spending almost £700. Now I'm having cancellers remorse. Arhhh!!

 

What did you add to bring it upto £700?
I added the 1080p and mine came to £650. If I dont like it I should easily be able to sell it for £750

 

Also the 1080p and the 9-cell battery, which seemed to kick in £20 shipping.

My PC use is 95% browsing and i-player with just a little audio editing, so I didn't need the 740, nor 435M. Realised that Optimus only applied to the i5 after making the purchase.

Ultimately, the longer lasting battery of the i5 would be more useful than the extra power of the i7, as I'd like to take it out to internet cafe's etc.

I'm going to wait for user impressions and, if good, buy it with the i5 or even wait for S. Bridge

 

You could well be correct but someone else here said that Optimus will increase battery life for browsing, so not sure who to believe

 

Alas I didn't get the £496 deal - mine was just the standard £165 off plus another 10% voucher. The spec is bog standard except for the addition of a Windows DVD.

 

I think you will notice better battery life.

i7 quad says it can "power down" cores, but it doesn't mean it isn't still burning - creating heat and consuming power.

 

Would a quad improve performance when browsing those websites that run a lot of flash ads?

 

there is a battery life difference. with i7 the main video card is downclocked but still consumes alot of power. With optimus it switches to the integrated graphics on the cpu which uses less power.

 

No seasalt I believe it won't. What will is GPU and Hard Disk speed. If, however, you had a really high clocking quad, it might affect web browsing?

 

I heard that Blu-Ray playback is very demanding on the computer. Which component is more important towards a glitch free playback? The processor or the GPU? Will the core i5 suffice for a smooth watching experience?

The reason I ask is I don't know how well Dell has designed the XPS for heat management. If the core i7 gets too hot during HD playback, I don't want the frames to drop. If there is one thing I hate, its sitting down to watch a HD movie and then realize you have to wait for the heat to go away for smooth watching.

 

My experience with i7-720QM and a Blu Ray laptop...

It had a graphics card just under GT 420M in the Notebookcheck.net ranking, to compare performance. 4GB RAM, 5400RPM HDD. 1366x768 Resolution.

When I first put the Blu Ray disc in, it lags like hell. It whines, and is kind of stuck in lag, and at first I think it can't play it. And this is a brand new computer. But give it a few minutes, everything returns to earth, and I can finally press play. It then takes a while, but once it gets started, it's good. No choppy play. But then this isn't Full HD. But don't expect being able to scroll around the length of the movie smoothly.

 

Have to add, I saw a screenshot somewhere of the new XPS 15 (GT 435M, 8GB RAM, i7 quad), with GPU Max temp at 79C, though it was not clear what processes were being run, or what tests or applications had been used. Apparently it is quite good at temp management (always a huge factor in any notebook purchase).

 

i5 and 420m will be fine for blueray.

Quad will only give you an advantage in heavily threaded apps (encoding/3d modelling etc)

 

Well... LaptopMag just finished their review for the Dell XPS 15 review and the battery life sucks even with Optimus according to them. I think since I want the GT435M its a no brainer to go for the quad processor. I just wish they allowed the GT435M with the Core i5

They also state it is hot even with a Core i5 processor. Obviously there is no heat advantage with the Core i5 either

 

Obviously there is an advantage. Clearly it is "hot" even with i5, so with i7 it'll be much much worse. Try using a few i7 quad laptops.

And, while I doubt Optimus and its "advantages" (not having the best software, running through Intel graphics, causing lag, not starting/shutting right, and flaws in general), i7 will surely make the battery run out faster than i5.

Agree, if they offered i5 with GT 435M I'd order one.

 

Normally I would say that how hot the insides get has no bearing on how hot the palmrest gets. I just had a gander at the manual and, sure enough, Dell was stupid enough to put the Hard Drive under the left side of the palmrest, and followed it up by putting the CPU underneath the left side, and topped even that by also putting the GPU under the left side.

Then, they topped everything with the proverbial maraschino cherry: they made the palm rest out of aluminum.

It's probably going to be hot. I wouldn't be surprised if the southbridge is underneath the touchpad (_again_).

 

This might be a positive, since the aluminum acts as a very large heat sink.

 

Lol! You make it sound like a cake with a bad arrangement of ingredients

 

I went with the Core I5, though I chose the 2.66ghz version. Main reason? Battery life. I already have an HDX 18t notebook that gets about 2 hours max. I need something that will do double that.

 

Oh no, the aluminium is not a large heatsink. It just warms up well, but does not dissipate heat very well at all, because it's not exactly a large piece of pure copper.

 

Aluminum is a good thermal conductor... Just not as good as silver/copper/gold. If I'm not mistaken, aluminum has around 10x higher thermal conductivity than steel.

 

That is if the whole laptop is unibody aluminum like the Macbook Having owned a Dell before, I can say for sure Dell will never match that quality of build.

 

I've found this an interesting thread , and would like to add in a few things .
1. I'm also looking at the XPS 15 i7 . I've noticed that Dell's USA site has most of these models with default memory as 6GB , and the UK site has them with 4 GB . Is the 6GB necessary here ? Possibly the Nvidia GT420M or more so , GT435M require more main memory to work well ?
2. Re the i7 - not claiming to be an expert on this - however , my understanding is , that even if you're , not multitasking , and not running apps specially written to take advantage of the quad-core , the Windows op/sys is utilizing it . Windows is obviously itself very multi-tasking and this should be felt by the app itself . e.g. when watching a movie , so the video player is relying on Windows to do all sorts of things for it .

 

Nor will Apple ever match Dell's price Anyway who needs a laptop that will last forever, we're all gonna upgrade in a few years anyway!

Anyways, I'd go the i5, lower heat and less power (longer batt life) - though I'm not a gamer.. so the call is yours!

 

My sig will attest to that!

 

The i7 in the XPS 15 seems to be exceeding expectations in terms of how much heat it emits. Does the i5 really run much cooler?

 

I think you are right about #2. If you open four single core apps, it should assign one core to each.

 

Hi! I have a similar question here; in my country (Chile) the default option for the L501X is an Intel Core i3 370m @2,4ghz, and the upgrade to the i5 460m @2,53-2,8ghz costs ~125usd, so... does it worth it?

I have to mention that, in kid of compensation, the 1080p screen upgrade costs ~20usd

Sorry for my english, and thanks in advance!

 

You will feel the difference between an i3 and an i5. Can't you choose the i7?
When buying a new laptop I would go with the better processor and the screen. Those are things you can't easyily upgrade afterwards.

 

I definitely went for the screen upgrade. But my doubt was on the processor: the harder task I will do in my notebook will be music encodig (along with more programs running in background like web browsers, etc.), so i tought that an i3 could fill my needs.

My main concern is about the processor temperatures; is it truth that the core i3 runs cooler than the i5? or they runs basically the same?

Thanks for your reply.

 

Yes the i3 runs definetly cooler but the i5 doesn't run that hot neither. i3 = low class, i5 = middle class, i7 = high class. I think the i5 is perfect for everyday needs and also future-proof. Maybe in two years your i3 is too slow for your needs... So pick the i5 if you can afford it.