How much more RAM does Windows 7 use than Windows XP?

Question

I"m trying to figure out whether I need to go with the 64-bit version of Windows 7. I'd rather not unless there's a big benefit just because one or two missing 64-bit drivers (or one app that doesn't work quite right wold be a lot of work).

Biggest reason to go with the 64-bit Windows 7 (that I can see) is letting you use more RAM. But I never max out my RAM now (despite simultaneously burning CDs, testing sw in Virtual PC (Windows 7 no less) and editing something in Microsoft Word).

Since Windows 7 has a minimum RAM of 1 GB (vs something like 64 MB for XP) that suggests that Windows 7 uses a LOT more RAM.

Answer 1

Do you have more than 2GB of RAM?

Yes? Then stop caring!

XP and 7 use RAM in different ways. Right now on my Vista box (Which has a lot in common with 7), I'm idling at 54% used RAM. That leaves me with under a GB! That's not enough left to, say, play Crysis. So let's turn my page file off. Very little change. Let's go play crysis anyway.

Ran great, and now I'm idling at 30% RAM. Vista and 7 cache in your RAM, because it's about 40 times faster than most hard drives (not SSDs though, it's still a lot faster, but not as much), so it makes a lot of sense to use it to speed up your PC.

If you have less than 2GB of RAM, stick with XP. Vista and 7 are much, much faster than XP if you give them modern hardware.

As for the minimum, XP never really ran well on 64mb of ram, and win7 can run on much less than 1gb. Seems like MS have changed their mind about how they want their OS to be seen. Back when XP existed, fewer people had PCs, and there was almost no widespread internet, so they could (basically) lie on the packaging and nobody would mention it. Now they've put a reasonable figure that will allow Win7 to run as designed (caching and all).

Answer 2

Using more RAM is not really a bad thing. Sure, the OS may use a bit more ram for larger OS images, but the real reason is that Windows 7 has far superior cache and prefetch performance compared to XP.

In general, if 90% of your RAM is sitting there unused, then your computer isn't taking advantage of the memory it has. While it's true that Windows 7 needs a bit more RAM to run properly, the real truth is that it will take full advantage of the RAM you give it, unlike XP.

Windows 7 will function just fine with less than 4GB of RAM, so you should be fine getting the 32-bit version. You just won't do quite as much caching as someone who had 64-bit and more RAM.

That said, frankly I think it's worth getting 64-bit. Many of us used XP for 8 years or more, so it's not far-fetched to think we might be on Windows 7 for five years or so. It's obvious that 64-bit is where computing is now. I'd rather replace a component that doesn't have 32 bit drivers than use a 32-bit OS just for that piece of hardware. On the application side of things, through Windows on Windows (WOW), there should be no issues with 99.999% of 32-bit applications running on 64-bit Windows. The application would have to be doing things in pretty stupid ways to be tripped up.

Answer 3

Depending what I'm running, I'm constantly at either 800mb or 1gb in idle. Whereas in WinXP it was somewhat between 500-800mb.

But then again, I'm running with 4GB (3.5gb effectively since I'm on 32bit) so the extra 500mb are negligible.

Answer 4

"testing sw in Virtual PC (Windows 7 no less)"

That reason alone, I'd be going with 4GB of RAM, which means 64-bit. XP lies to you about how much RAM you are using. It actively pushes data out of memory and into the page file when it's idle, even when you have memory free. 7 on the other hand actively caches data into your free memory space that you may potentially use, since MS smartened up and realized there's no reason for it to not be there. Having "free" memory is a waste.

Does the core XP OS use less RAM then 7? Yes. But it's all the other software that people install and run that really makes a difference in how much RAM gets used.

In short, do the basic research, and see if your hardware has Win 7 x64 drivers available. As for your software, I have yet to encounter something that doesn't work. The only thing I'd think to be worries of is if you're running some software that work with the hardware at a really low level. If it looks like x64 will work, use that.

Also, how do you plan on purchasing your upgrade? Retail upgrades give you the option of doing either 32 or 64 bit as you see fit. So you can upgrade to Win7 x86 now, and if you purchase more RAM later, you are still licensed to run the x64 version. You'll just have to do a re-install.

Answer 5

Molly (i think) i installed windows 7 on one partician and xp pro on the other partician on my dell lap top. I'm using 512 m of ram on a 64 bit machine. True, I need much much more, but both do seem to run alright. With windows 7 though, you have to be very careful about over loading it because it WILL freeze up. But for ordinary use, 512 is fine and generally 7 is alot better than xp. And (pardon my french) and hell, windows 98 was better than vista.

Answer 6

Google Tweak-XP Pro. It allows you to change the amount of ram WinXP caches, up to 1GB. If you don't want the pagefile, make it down to 2MB[minimum].

Answer 7

7 Home will idle on as little as 275mb of RAM. The O/S needs a good bit more than this to support the usual services and extras that most people will be using (or allow to run), as well as to (put in layman's terms) "do it's thing". The "average" 7-Home user will generally require about 600-650mb of RAM for W7 to load up everything that it's using and to be able to (again in layman's terms) "move around" without any bottlenecks or other slowing down.