Moore's law and choice of computer purchase

cepheus

I've just had my usual 'crazy pub argument' this lunchtime. This time it's about laptops or computers more generally.

My opponent's view its always worth getting a top grade computer since it will remain useful for longer. He is bragging that his laptop (bought just before XP came out possible 10 years ago?) is still better than the cheapest laptops on offer today due to the ability to upgrade. It cost him around £1300 then.

My view is that top grade computers are a waste of money. Moore's law implies speed and memory double every two years and it would be faster OR cheaper overall to buy 2 cheap computers (one every 5 years) rather than one expensive one every 10 years. Looking at the sub £300 laptop page I notice some of these models are upgradable. Reliability might be a disadvantage with cheaper brands though.

Do you have any evidence to support either view, such as a graph showing expensive and cheap models along with spec for year.

Hammyman

The rule of thumb is buy the fastest you can afford. Whilst Moores law states that the MAXIMUM speed of processors doubles every two years, it doesn't mean that computers have them installed. The Intel Pentium Dual T3400 and T4300 common in lower spec laptops is SLOWER than Intel Core 2 Duo processors released and installed on mid range laptops FOUR years earlier.

In regards to memory, 2GB is more than enough for most people.

As for the one expensive every 10 years vs two cheap ones every 5 years, I'll say this. I'm selling 5 year old Dell Latitude D610's (original rprice over £1k) that still have over 2hrs use on the original battery and have no faults and are still well usable today for general browsing, email, IM, Office. OTOH a cheapy will be lucky to have a battery that lasts 18 months and I've repaired loads of cheapy ones under 2 years old with overheating faults, charge socket faults, missing keyboard keys, seized hinges etc. You'd be lucky to have a cheap one last 5 years. In addition the new Celeron based ones, like the Asus X5DC are SLOWER than the 5 year old Dell D610.

esuhl

I guess you'd need to calculate the price per floating-point operation or something.

Look at the price of DVD players - when they were new they were very expensive, partly because "early adopters" are willing to pay over the odds for bragging rights and partly because fewer machines are manufactured. As they become more popular, economies of scale make the devices cheaper and more common, and the increasing demand means that the market can support an increasing number of manufacturers. More competition results in more competetive pricing.

So, it seems clear to me that the newest hardware will always be disproportionately expensive, giving less value than cheaper components. In terms of bang-per-buck (as the yanks would say), the "sweet spot" is somewhere between outdated and cutting edge technology. If you look at the latest/best mainstream hardware, then wait until it has been superseded, I've often found that this represents the best time to buy. Unfortunately I don't have any figures to hand that will confirm this!

I also find it better to get decent core components (PSU, case, fans, DVD drive, etc.) that will last for many years, and just upgrade the motherborad, CPU, RAM and graphics card. That way you can effectively upgrade to a new computer with good quality components for the same price as a pre-made PC with not-so-good components from a high street retailer.

free4440273

It's the law of diminishing returns / does the ordinary punter absolutely need the fastest/latest whizz bang processor/clock speed/ graphics? Probably not// I tend to ignore the nomenclature and decide what will work best for me and my requirements //

ddoris

537 - http://www.cpubenchmark.net/cpu_lookup.php?cpu=Intel+Pentium+M+2.13GHz

1417- http://www.cpubenchmark.net/cpu_lookup.php?cpu=Pentium+Dual-Core+T4300+%40+2.10GHz

You can't future proof a pc. You can easily waste money.

globalds

I was looking around for graphs and found this site

http://www.singularity.com/charts/page70.html

Loads of graphs relating mainly to technology.

This sites seems to be dedicated to the technological singularity.
All good stuff but not as up to date as I would like.

cepheus

So what is a typical fast speed and a slow speed at the moment?

These cheapos look around 2GHz

http://www.moneysavingexpert.com/deals/cheap-laptop-deals

4743hudsonj

cepheus wrote: »

So what is a typical fast speed and a slow speed at the moment?

These cheapos look around 2GHz

http://www.moneysavingexpert.com/deals/cheap-laptop-deals

Its not as easy as that, i have the higher mid end i7 Q740. Its clock is 1.75Ghz. But then again its quad core and can "turbo" boost to 2.93Ghz (i think?) on a single core.

The numbers mean nothing unless you understand the implications of certain models.

Another example is that because its an i7, by default the Motherboard supports DDR3 RAM. Whereas the cheapos will mostly use the now superseded DDR2.

diable

Ask him if he upgrades his Wife/GF as often as his computers?

prowla

Moore's law originally stated that the number of transistors on a chip would double every two years, but PC CPU performance does seem to correlate (maybe by design).

You only need the latest and greatest for gaming, not for surfing the web and office apps.

epninety

Slightly sideways view, but my computers are work tools - if it takes me a day to setup a new computer with everything I use, copy over user data files etc., that's a day of lost earnings. That can easily exceed the cost of a run-of-the-mill desktop or laptop. For my daily use CAD machine, getting everything back to 'just so' and ensuring I didn't lose anything on the way might easily take 2 days (well ok, probably one 16 hour day), and exceed the cost of a high end machine.

You have to work out what you think your own lost time is worth, but it's worth considering when you make your purchasing budget.