Borrowing from a distinguished member ...
Originally Posted by ganzonomy
A lot of people asked me if for windows vista 64-bit, if it is worth it, now or at any reasonable point in time, to go beyond 4GB of RAM in a laptop. Arguments for greater than 4GB RAM include more room for superfetch to pre-load programs to memory, greater stability both overall and when running heavyweight programs, and more “available gaming memory” according to the quasi-benchmark known as the “Vista Experience Index”. At the same time, those who decry going beyond 4GB state the lack of 64-bit native programs, the cost to upgrade to 4GB SO-DIMMS to accomplish “64-bit only amounts of RAM”, and that it will effectively prevent returning to 32-bit OS's without retrofitting the old memory. Having taken my Sager NP8662 from its stock 4GB DDR3 RAM to 8GB DDR3 RAM, and having a little time to assess things, there are observations both positive and negative, that have surfaced as a result of the upgrade.
First, the most obvious positive affect of upgrading to 8GB or more of RAM is that programs are more responsive. Perhaps this can be attributed in part to SuperFetch, a component of Windows Vista that pre-loads your most used programs to memory during start up. If such logic is deemed valid, then more memory obviously makes a happier SuperFetch (and thus, Vista). From what I've gathered, I believe that Firefox, AIM, and OpenOffice.org have been SuperFetched, as over time they have started up with increasing alacrity and less waiting. At the same time, SuperFetching with 8GB really has not slowed down the startup time of the computer, which means it apparently is sufficiently seamless so that in the right (read memory-favorable) circumstances, you won't notice it working in the background quietly loading programs. A little more time pre-loading from the hard-drive to memory means that once in memory, the program opens nearly instantly. (RAM is an extremely fast storage media, it just needs to be kept constantly powered in order to prevent loss of data.) Such copious amounts of memory, combined with SuperFetch thus becomes useful when opening large applications that concentrate on artistic manipulation, scientific and/or mathematical calculations, music production, etc. Who really wants to wait for a hard drive to spin about wildly as a “minimum of 1GB or more” RAM sized program slowly awakes from the Hard Drive? It's loaded during startup based on your usage amounts, you click it, it starts up in a few seconds, you're in business. The same logic applies for laptops with 12GB or even 16GB of RAM, just with more room to pre-load programs. With Vista, what once was considered “wasted memory” in XP, gets put to use pre-loading programs.
At the same time, all this memory has to come at a premium. Finding 4GB SO-DIMMs to make 8GB kits is not cheap. The least expensive I could find a Corsair 8GB DDR3 kit was for $750 at NewEgg, and even DDR2 667MHz 8GB kits hover at around $300. Attest this partially to the difficulty of putting 4GB of storage on a small chip, and partially to the pride of companies that can actually pull off such density. (I'd like to note here that if you buy a company's memory such as corsair, and it says Hynix or Apacer or whatever on the chips themselves... Hynix and Apacer make the chips, and Corsair with its naming power puts its name on the chips and sells them to the public... people know Corsair as a premium brand, but Hynix and other semiconductor makers usually get a “?” look from the general public.) Compare this amount to the $90 to $110 that 4GB DDR3 1066MHz Ram kits goes for, and the $50 to $60 that a 4GB DDR2 kit command, and you can see why the idea of a 4GB SO-DIMM is not commonly found in laptops outside those designed for gaming and workstation use. The cost / benefit analysis just isn't there to really justify the price punch at this point in time. An extreme example could be the 16GB upgrade available in the Dell Precision m6400, and the 12GB upgrade in the Sager np9280. By maxing out the memory at their respective limits, potential buyers are looking at between a $1,300 to $2,500 upcharge simply for the bragging rights of “I have more memory in my laptop than you do!”... to which most users will simply shrug off as “why?” Some people may say “but it allows me to future-proof my system!”, but the same $750 per aftermarket 8GB DDR3 SODIMM kit, or even $300 for its DDR2 667 counterpart could arguably be better used for upgrading parts such as the CPU from a dual-core to a faster dual-core / quad-core solution, a faster and bigger hard drive, or solid state drive (depending on the cost for both), or if your laptop allows, a better video card. There really has to be a great reason to justify such an upgrade, and how many programs really can fully fill an 8GB or 16GB RAM-Laden computer? For the average user, I presume very few.
While we're on the topic of performance upgrades, Vista and Windows 7 have a component of their experience index known as “gaming graphics”. This component is a combining of what the dedicated GPU (if applicable) and the “shared system memory” are. Admittedly, the “Experience Index” is far from an end-all for determining a great computer for high-end and gaming applications, but to have a bounty of memory for a computer to dip into during 3-D intense applications is never a bad thing. Think of it as “stem cell memory”; that is memory that can be used for anything, and it happens to be available for use in a game should the GPU ever require it. It could be memory that's takeable from programs that are superfetched (for when you need a memory boost for a game), or just sitting around doing nothing in particular (as the used for current programs + superfetched programs) could be less than what's the total. Comparing 4GB to 8GB, the amount of this “gaming memory” goes up from approximately 1.5GB of system RAM used to 3.5GB system RAM being used. (In fact, on my Sager, the amount of gaming memory is 4,606MB RAM... 1,024MB is dedicated from the GTX 260m, and 3,582MB is system memory that can be switched to help the dedicated GPU.) What effect this extra RAM has depends on the game and whether it can actually use the system memory, as well as if it's even needed at all. If you have more than you need, and the aforementioned SuperFetch and the system isn't using as much as it can, you still have memory going to waste, which reduces the justification of spending the large amounts of money to attain 8GB or more of RAM. Imagine a program that can only use a single core, and you're working with a quad-core. This is not unlike having 16, or even 8GB of RAM for a program that at most can or will only use 1GB of RAM (video or otherwise). The rest of the bandwidth and available space is simply being put to waste and being used to occupy programs that are merely fetched, and not in active use. How many of us really want to face the possibility of having too much RAM that's being wasted, just like when one had 4GB RAM in windows XP as an early adopter of “maxing out 32-bit ability”.
Well fortunately, those of us who have more than 4GB RAM are smart enough to have a 64-bit operating system and a motherboard platform that can handle the 64-bit addressing abilities of 2^64 bytes. While the vast majority of programs are still 32-bit, and can only take 2GB RAM for themselves without crashing, with the advent of > 4GB RAM and 64-bit architectures entering the mainstream, programs can now more fully utilize this newly available RAM and thus more complex applications with larger instruction sets will become the norm. Realize, that a 64-bit chunk can carry twice as much information as a 32-bit chunk and is not as “memory restricted”. A side bonus is that, at least with Windows, 32-bit programs run seamlessly with 64-bit programs, regardless of whether there's 4GB of RAM or more inside. (In fact, some 64-bit native programs will use more than 2GB RAM at any given time, and thus the extra RAM becomes no longer a luxury, but a necessity.) I could only imagine how those who run scientific programs felt when 64-bit architectures and more than 4GB RAM meant that programs wouldn't max out when 2GB were used. I find that within 12 to 18 months, 4GB will be the standard of all laptops, and 8GB, if not more, will become commonplace in mid-level laptops, with triple-channel leading gaming machines and portable workstations in greater presence. Laptops are slowly becoming desktop replacements at various levels, and most companies know this.. with this advent, the difference between desktop and laptop is slowly closing (although I doubt it will ever become 1:1 level), and the number of people who own computers with more than 4GB RAM is growing. The end result will be prices will come down, giving more people a justifiable reason to fully abandon 4GB and 32-bit limitations for a 64-bit and greater than 4GB world. The performance, gaming, complex workstation applications, and the architecture is ready for it to take over, all that needs to take place is a greater embracing by the computing public, and for prices of memory to come down from the ivory tower in the same fashion SSD prices have plummeted. It's just a matter of time.
(And if you're wondering, yes I'm one of those dolts who upgraded early to 8GB DDR3, and these are some of the observations I've noticed with my computer, as well as those of my friends who have 8GB and more.)