You need a 64 bit operating system. Any 64 bit operating system will work.

You know whose fault that is? Yours.

For normal, right minded people, this is merely the second page.

Lol.

If no one has mentioned this so far, XP 64 bit was a horrid mess with no driver support, DO NOT EVER CONSIDER XP 64 BIT FOR YOUR OS!

I just found this table and was amused (in the "and people wonder why I prefer Linux" and shaking my head kind of way)

Physical Memory Limits: Windows 7

Version/Limit on X86/Limit on X64
Windows 7 Home Basic / 4 GB / 8 GB
Windows 7 Home Premium / 4 GB / 16 GB
Windows 7 Professional / 4 GB / 192 GB

Arbitrary memory limits GO!

I had no idea they did that, how lame! (not like most consumers would ever notice a 8GB RAM limit, it's still a ton for every day use).

Yes I hate that forced obsolescence with the memory limits. Microsoft flaunting its monopolistic control of the desktop. Also considering how insanely overpriced windows is, I really wish linux would take over. But you need commercial developers and they seem content with putting out games/apps for Windows.

Just curious how do I mark the topic as solved?

you need to check
1) how many DIMMs your mobo supports.
and
2) dual/triple/quad channel?
3) data rate? 1333 1600 etc
and when you finally buy your memory, remember to set the speed correctly in the BIOS. and then test each stick in memtest86+ for at least 1 pass, to see that it is ok, then if they are ok, run them together and again memtest86+

M$'s intent isn't really to screw the consumer, it's to protect their pricing in the high-value accounts that buy the "Professional" editions. They want to make the "Home" editions so unattractive to the "Pro" purchasers that they won't consider going downmarket.

The result is still that the high-end consumers get screwed. But that kind of collateral damage just isn't part of their calculus.

You can't. You didn't mark the topic as a question when you created it.

Well that sucks. I'm glad I have Win7 pro "five finger" version then....as it seems to support the most features. Screw M$ btw, and their insane pricing schemes.

AFAIK those were never licensed outside of enterprise.
XP was 32bit and I don't believe that you can get a legally licensed version of XP 64 for home use.

My 1st post in this topic was about 64bit system so is next about XP (just not mentioned "64bit" tag). Indeed, if I remember correctly you couldn't buy boxed edition of this system, but it was available in OEM versions / by licensing agreements also for use at home.

Yes, I wasn't too serious about XP (since it had a lot of troubles with drivers and hardware compatibilities) but, as I mentioned in previous posts, at time of posting that I wasn't aware what kind of PC is owned by OP and also even if it's hard to get it was still worth to mention as one of options.