Laptop processors - Intel v. AMD
 

I am shopping for a new laptop for the mrs. Likely will be a Dell - she has one now and likes it and we have had little trouble with it.

They have either the AMD or Intel processor configs. How do these compare?

In particular the alternatives would be:

Intel® Core™ 2 Duo T7250 (2.0GHz/800Mhz FSB/2MB cache)

OR


AMD Turion™ 64 X2 Mobile Technology TL-58 (1.9GHz/1MB)

She does pretty standard user tasks - email, web-surfing, music - but is also a heavy PS3/Lightroom user as she is a Photog.

The price difference between the two variations nets to around $100 (intel dearer).

Personally I am an AMD fan. I think that it is great that in a few short years another U.S. company was able to equal and surpass Intel while doing so for less money per equal unit of performance.

If it weren't for AMD offering an equivalent option, Intel's monopoly would have resulted in much higher processor/computer prices today.

Having said that, right now Intel's laptop Core 2 Duo is one hell of a processor. It is equal or faster than the equivalent Turion and generally uses less power -very important in a laptop where battery life and heat are serious issues.

I am surprised that you found only a $100 difference because as a part the Intel processor costs about $200 more than the equivalent AMD.

Generally speaking the AMD will perform a bit better on office apps like Word, Excel, etc. and the Intel will perform better on tasks like processing video, high-end video games, etc.

If you are looking for more-than-adequate speed at a great price go AMD, if you are looking for best possible performance right now - go Intel.

While generally an AMD fan also, pretty much every hardware review site (sorry, too lazy to look them up) ranks laptop processor performance this way, from fastest to slowest:

Intel Core 2 Duo Extreme (Conroe)
Intel Core 2 Duo (Merom)
Intel Core Duo (Yonah)
AMD Athlon 64 X2 T-xx (higher numbers are faster)
Intel Celeron M & AMD Sempron - toss up

In Core 2 Duo, the T series is fastest, followed by the L series and the U series. The U & L series are not used for performance but for low energy use and heat output. In both Intel and AMD series, higher numbers give better performance (and cost more), e.g., Core 2 Duo T7600 will be faster than T5600.

Note, this is laptop only. I still prefer AMD for desktop processors, mostly because of the bang for the buck.

Is she contemplating a lot of portable use?
 

If so, the only figure of merit that deserves consideration is battery life.

Unless a laptop is going to be used a lot for computation-intensive apps as a substitute for a desktop, the only thing that matters is how long it will run before requiring a recharge. It amazes me how users beg for more and more CPU and GPU power, and then are disappointed when the sucker has to be plugged in everywhere they go - as if their supercomputer-with-a-handle didn't devour batteries.

For my portable word processing and email, I use a 386/16 with 1024k that will run all day without recharging - and it has a spare battery pack that can be populated with 8 throwaway AA cells.

If I'm going to be doing Windows application development on the road, then I take the Vaio - and plan on swapping the battery in two hours. P.I.A.

For laptops, Intel all the way.

I not only read every site when making the same recent decision, but actually tested equivalent procesors on the machines I wanted in store. I found no discernable difference WHATSOEVER and actually gave the slight advantage to AMD as it was a bit faster in several applications and processes (including a video editing related program/file) I tested. As the AMD machine offered a lot more bang for the buck, (more like a $400-500 savings I opted for the AMD and am not disappointed

Whilst I agree about battery longevity, how does this affect processor choice in this case? And isn't the Intel supposedly less power hungry and thus allows batteries to last longer.

She doesn't really do all THAT much portable work - it's a 17" laptop - not exactly a road warrior model :D It's her desktop replacement ( we don't have desktops in the family).

As for applications, the most common use if Photoshop/Lightroom - does that qualify as "computation-intensive apps"?

I am an AMD fan but moved away completely once the Core Duo/Core 2 Duo series came out. They run cooler, are equivalent or faster in performance, and are excellent at balancing power use with performance. It's that power management that's vastly superior to AMD who is quite a bit behind in the laptop stakes at present. As a desktop replacement the AMD should be OK but IMO the Intel is a better choice.

For Photoshop/Lightroom you'll get a much bigger bang for your buck by maxing out the memory.

I don't think it's possible to generalize about brand and power hunger. It varies from one CPU generation to the next. And since I try to buy technology "behind the price curve" (getting last year's model for half the cost of this year's), I'm not very concerned with the latest and greatest processor technology wars.*

In any case, I'd rather have a marginally obsolete AMD that used less power than a brand-new Intel.

(The first CPU chip I owned was a Motorola 6800 that cost me $375 in 1976.)

* This strategy also finesses the "low serial number" syndrome that often afflicts bleeding edge technology.

Bad choice in this case considering the older Core Duo machines are already very cheap and are now 'last gen'. The first Core 2 Duos are getting there. IMO it's about finding a good brand/price/performance balance. It's always easy to pay too much to get a 'value' in old technology. It's much harder to find the best deal on later technology but is possible.

Memory is so cheap now there's no reason NOT to stuff a laptop to it's maximum.

The best deal on later technology always depreciates faster than the best deal on earlier technology.

There is a reason if it's made by Sony. If you max out its RAM, it creates more heat that the machine was designed to dispose of. The solder connections in the SODIMM slots go bad, and you have to repair or replace the sockets. "Bleeding edge."

Totally concur. I use several of Adobe design suites including PS CS3 and LR2. Do max out on main memory (4 GB up preferred), and a large capacity drive with min 7200 RPM (may be hard to find for laptops). Be sure the laptop supports an external flat panel monitor (like a 24").
I will go with AMD (dollar for dollar; given same performance)

Keep in mind that the rotational speed of a hard drive is only one of the determinants of throughput - the aggregate data transfer rate is limited by the speed of the interface and seek time. If interface is slower than the drive, kicking it up to 10,000 RPM won't make anything happen faster.

I get a kick out of people bragging about their 7200RPM laptop drives when I know they're running them through an IDE interface designed for 4200 or 5400.

So i went with Intel given the better reviews, power consumption and performance and only $100 difference. Here are the specs:

Inspiron 1720, Intel Core 2 Duo T7250, 2.0GHz, 800Mhz, 2M L2 Cache
Expresso Brown Color with Microsatin Finish
1GB, DDR2, 667MHz 2 Dimm
Anti-glare, widescreen 17.0 inch display (1440 x 900)
Intel Integrated Graphics Media Accelerator 3100 Inspiron 1720
120G 5400RPM SATA hard drive 5400RPM
Microsoft Windows Vista Home Premium Edition, English
Integrated 10/100 Network Cardand Modem, for Inspiron
24X COMBO CD-RW/DVD
Intel 3945 WLAN (802.11a/g) Mini Card
Integrated 2.0M Pixel Webcam
56 WHr 6-cell Lithium Ion Primary Battery, Inspiron 1720
MS WORKS 8.5
1 Year Limited Warranty
Dell Wirless 355 Bluetooth Mod

$869 + $71.68 tax

So the one thing I am going to buy is more RAM. Does any memory fitting the above description (ie "DDR2, Dual Channel 667MHz 2 SODimm") do/fit or does it need to be specific to Dell. Does it need to have specific number of pins?

Buy as much memory you can afford or the laptop will support. You can go to just about any memory manufacturers website and easily choose the correct sticks. The site will do all the work for you.

Get a dedicated video card.

Oh, a fifty-six watt-hour battery? I think that means that if the computer as a whole (CPU plus peripherals) is drawing 56 watts, it will run for an hour. Can someone tell me if that interpretation is incorrect?

Yes - RAM modules are happiest if they fit the sockets, so the number of pins is non-negotiable. Any reputable memory with those specs will work fine. I have used aftermarket memory from Kingston, Crucial, and Patriot with no problems.

Watt-hour battery pack rating
 

Your interpretation is correct that 56 watt-hour battery pack will yield one hour battery life if notebook PC consumes 56 watt-hour energy. But most notebook PCs range from 15-30 watt-hours in total power consumption. Some processors are cooler than others, specifically Intel processors rated as ULV (ultra low voltage) are the coolest, compared to non-ULV Intel & AMD processors. I don't believe AMD offers ULV processors yet.

I would like to see some of those. According to http://en.wikipedia.org/wiki/CPU_power_dissipation, many mobile CPUs draw that much alone, and the total has to account for the graphics processor and display lighting.

A couple of things to keep in mind, [1] the motherboard and chipset you have use a dual-channel memory config. When using more than one DIMM you will get noticeably better performance by insuring that both modules are exactly the same; same capacity and same bus and operating speed and [2] Windows XP Pro 32 and Vista 32 will only recognize up to 3 GBs of RAM. You have to go to XP Pro 64 or Vista 64 to get OS support for more than 3 GBs.

My [specific] advice would be to simply go to www.newegg.com and buy [2] 1-GB sticks of Corsair ValueSelect RAM, 200pin SO-DIMM PC5300, 667MHz - great price - great RAM - done.

Thanks - I got very similar advice on notebookreview.com. Almost all memory is the same, despite some sales people insisting i need to get dell specific memory :rolleyes:

Look for DDR2 800 SO-DIMM memory modules. All DDR2 SO-DIMM modules have 200 pins. They are a commodity, so you can take advantage of commodity pricing on them.

Any of them will work. DDR2 800 is the sweet spot right now, plus that matches the speed of your FSB. Buy a matched pair of memory modules to take advantage of dual channel memory and replace both memory modules at the same time.

The i1720 can take up to 2G per slot. So you can upgrade to 2 x 1G or 2 x 2G.

Something like this will work just fine (2 x 1G):

http://www.newegg.com/Product/Produc...82E16820146722

Or two of these (1 x 2G each, because it's cheaper to buy them separately right now):

http://www.newegg.com/Product/Produc...82E16820227250

Memory is ridiculously cheap these days. You can pay more for exactly the same thing made by another company, but you won't be able to tell the difference (assuming the same speed, CAS latency, etc).

Save the original memory modules in the plastic package the new ones come in, just in case you need to return your notebook for service. In that case, remove the new ones, put the old ones back in and then send it in for service. There's only one small screw to remove on the bottom of the notebook to expose the memory slots.

-David

Thanks.. I think the speed of my memory is PC2-5300 667Mhz, so why would I go for faster RAM if I can't take advantage of it?

The motherboard will just slow faster RAM down to 667.

The only reason for buying/using faster than spec RAM is if [1] the faster RAM is the same price as the spec RAM and [2] you foresee yourself upgrading to a laptop with faster RAM/FSB speeds in the very near future.

right thanks. Well neither holds true so I am sticking with 667Mhz RAM.

Your FSB is 800Mhz. That's what you said in the OP.

The memory that they shipped with your laptop is slower than 800Mhz. I said in my post "DDR2 800 is the sweet spot right now, plus that matches the speed of your FSB." That means your front side bus is capable of supporting DDR2 800 memory, but they shipped it with slower memory in order to save a few bucks. Since you're planning on replacing the memory, you might as well get the fastest memory your laptop processor will support. But you can go with the slower and slightly cheaper stuff if you want to. Either one will work, but for that matter, Dell branded memory will work too, but you're not buying that because presumably you have become an intelligent and informed consumer.

Go with whatever you want. It won't matter to me. :)

-David

This isn't necessarily true - at least not in the way you intended.

Many motherboards [north/southbridge chipsets] and CPUs have stability issues when running at 1:1 with RAM - particularly with less-than top-of-the-line RAM.

In fact until recently if you wanted to run 1:1 you almost had to use very expensive and part-specific validated RAM.

I for one have no problem believing that Sony, Dell, et al run RAM out of sync with the FSB simply in order to make their systems more stable.

Of course increased stability means fewer BSODs and fewer CS and on-site tech calls [which means they also save money] but this can be a good thing for the consumer and only a small fraction of theoretical performance is lost.

Well, the laptop manufacturers design their systems based on the specs of the chipset, the CPU, and of course the RAM. They aren't going to ship anything that will fail out of its normal tested range. It's really simple: if RAM running at such-and-such a speed will work as tested at spec at given corners (room temperature, etc.) they will sell it; if not, they won't. It's not a matter of making "judgement calls" about stability or number of blue sceens. It meets specs or it doesn't. Computer design of the innards nowadays is largely a science, not an art.

If a design meets specs, then marketing decisions are made as well cost decisions. Slower RAM may be sold in a laptop to save a few pennies (remember, a few pennies here and there all add up especially when millions of units are shipped), and for marketing reasons they may want to sell faster RAM in more expensive systems. It's one more thing to help justify charging more for higher-end systems.

If there are stability issues with faster RAM, then the BIOS will limit the speed to the slower speed. I looked up the specs, and I don't see anything preventing it from working with DDR2 800 memory. In fact, the configurator at crucial says it supports both speeds. The chipset and the CPU both support 800MHz fsb, and it's advertised at supporting the 800Mhz fsb.

Usually problems like not being able to run 1:1 are when chipsets are new and new CPU lines and architectures first come out. The components in this notebook are not new. It's a very mature CPU and chipset. Plus, I would think it would be easier to run 1:1 vs asynchronous.

-David

I don't believe that at all. Certainly when you buy a notebook from the ODMs, it will usually come with the 1:1 or faster memory, and they use the same components and maybe even the same manufacturing lines to build the products.

Maybe when a new architecture or line first starts this might be true, but the BIOS can handle it and they solve those problems relatively quickly these days.

Dell and Sony do it to save money. (Arguably, to be able to sell the product cheaper in the basic configuration.) Plus, if they order all the same parts (same speed, etc) they can get a better deal on them, and play the commodity markets using larger numbers.

I think you and I had a bit of this discussion before, when you argued that the difference between the 533Mhz shipped with the Sony SZs at the time, was not all that different from the 667Mhz memory they were capable of supporting. I didn't like the fact that they were shipping the slower memory to save a few dollars on a relatively high end machine.

And BTW, 800Mhz isn't really 1:1 with the cpu clock. I think it's 4:1 (or 1:4 depending on how you look at it.)

-David

There may be more to it than just a few dollars. Sony has been struggling with heat issues in its Vaios ever since the PCG-F series, and they may have found that memory faster than 533 mHz would overheat the machine and either unsolder the SODIMM sockets (which the GRV/X/Zs are famous for) or cause the power management software to shut it down.

You could be right, but I don't see the SZ in that list, and that's what we were talking about. The hi-end SZs sold at a relatively high end price. But it could be a lot of things, like power consumption, battery life, etc.

-David

And that was my point.

'Stability' is a 'for example', it involves all of that, heat, battery life, performance, shutdowns, etc.

My point with the SZ and here is simply that the cost differential between [then] 533 and 667, and [now] 667 and 800 is so tiny that if Sony could or whomever could use the fastest RAM available without any heat, battery, performance, or stability issues they would because they could then advertise, "We use the absolute fastest RAM available for the best performance" or some such and that IMHO would be far more valuable to them than the few cents saved by using 533 instead of 667.

ok, I got your point. :)

I just think the last paragraph of your reply is subjective and it's not really based on facts. It's based on assumptions. Still, you could be right. I just don't trust them as much as you do (based on past incidents, not just at Sony), and I think if they can save a few dollars in what really comes down to commodity pricing for the most part (except maybe for the high end SZs, because they were able to command premium pricing) then vendors like Dell, Sony and most of the rest of them will do whatever they can to save a few dollars. A few dollars saved can amount to a large share of the profit on a large run of systems.

Getting back to the original topic ...

If it were me, I'd buy the DDR2 800 memory, but it's not me and it's not my laptop. Even crucial claims it will work, and if you bought it from them they would guarantee it. I believe it will run fine at DDR2 800, but I don't have that computer to prove it, so that's my opinion. For all my other laptops, I buy the fastest memory that the motherboard and chipset will support. In many cases, you end up buying faster RAM than the motherboard and chipset will support because they don't even make the slower speeds anymore, and if they are available, they are more expensive than the higher speed stuff. That isn't the case here, because DDR2 is still the current mainstream memory product.

-David

On another board I am informed that although the chip set is rated for 800Mhz it only supports max 667Mhz so that's what I am going with.