About to build new machines... 32bit or 64bit OS?

Stargazer

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Hi,

I'm about to commence two new PC builds. I've got all the hardware sorted out and will be placing orders shortly, but it has been 6 years since I did a fresh build and there's been a few changes since then.

One of the new machines will be equipped with an Intel i7. I've been told that this will require a 64bit OS. This isn't an issue if it's true because I won a copy of Win7Ultimate a couple of years ago that I've never been able to use.

The other machine will be running an Intel i5. Now, I'm only guessing that will require a similar OS but how do I tell for sure? There's a lot of things said about these chips that I don't really understand so I'm hopping someone here can tell me straight.

Is it essential that my i7 tower be loaded with the 64bit windows or is it just a recommended option?

&

When we buy an OS for the i5 tower, will that need to be 64bit as well?

Many thanks,

Rob.


 

Alexys

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On the wrong planet. ;P
Generally, you don't absolute *have* to install a 64-bit OS just because you have a 64-bit CPU—they normally have backwards-compatible instruction sets, so a 32-bit OS will work just fine. You *do* have to install a 64-bit OS if you want to have more than 4GB of RAM in the computer, because that's the maximum a 32-bit OS can address.
 

Stargazer

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Aha... So it's a memory thing...

Fabulous, thanks for the info. I'll be sure to go 64bit then in both cases.

Thank you,

Rob.
 

tmesis

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Alexys is spot on. You can work out the RAM capabilities in a simple calculator: 32-bit processors can access 2^32 different values (approx 4.29*10^9 = ~4 GB RAM). 64-bit processors can reference ~2^64 bytes of RAM or 18 exabytes... at least theoretically. Probably be a while before it's available in the shops to try out.
 
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