How to Upgrade to 64-bit OS?

Ok, so I know this question only partially belongs here, but I'm in a bit of a bind and I'm hoping someone can give me some simple advice. I bought an old HP Pavilion a6400f PC (32-bit Vista OS) for my 8-yo daughter just so she can play one of her favorite games. First obstacle, I needed to upgrade nearly everything except for the mobo. Ok, no big deal - still cheaper for me in the long run. I've built my own A/V rig in the past, so I figured it'd be fun to take this on. Researched everything - the GPU, RAM, CPU, PSU - to make sure it was all compatible, etc. However, the final obstacle that I haven't been able to figure out is what I should do about the OS in order to upgrade it to 64-bit. Like I said, this was cheap (estate sale), and there were no discs that came with it. So, I'm stuck with a 32-bit Vista OS. My question....

- Should I upgrade to 64-bit Vista OS or 7? (Keep in mind, this is a 'junk' PC, just to get my daughter by for a year or so.)
- If 64-bit Vista, how??? I've googled it and I'm a little unclear on whether I can do this for free.
- If 7, my A/V rig has 64-bit 7 Pro, but I doubt I'll be 'allowed' to use that license to install it on a second PC.

Just trying to get by spending as little $$ as possible :) Thanks for your time!

Thanks so much for the reply!!

What started this is that the game that she LOVES looks like crap and is almost unplayable on her PC currently. So, the reason it looks horrendous is because of the stock GPU (or lack-there-of) that it came with. It (the game) recommended the older GeForce 210 series. Fine, no problem. But of course, once you upgrade one area, it starts a chain-reaction. The only reason that I'm still trying to follow through with this is because all the upgrades are fairly dirt cheap and I thought it'd be fun (which it is). Another main reason for upgrading to a 64-bit system is so I can utilize 4 GB of RAM and more.

So, once the upgrade is finished, this is what my daughter's PC's specs should be (and yes, from what I've read & researched, the mobo supports a 64-bit system):
OS: 32-bit Vista -- original OS that came with PC
MoBo: IPIBL-LB (Benicia) -- original mobo that came with PC
CPU: Intel C2D E8500
GPU: GeForce 210 series
RAM: 4GB-8GB of RAM (it currently has 3GB, so I just ordered a couple of 2GB 'sticks')
PSU: 400w

I really appreciate the advice, but this PC just has to get my daughter by for another year or two, and by that time, she'll get an upgrade in the form of a hand-me-down from another family member. Spending $100 on another license for 7 isn't a wise choice for me. I might just give it a shot and stick with the upgrades I mentioned, but leave the OS as 32-bit to see how it handles the game. Then I'll decide whether to purchase a Vista 64-bit installation DVD from eBay and do a clean install. It may seem like a lot of work and a hassle, but I enjoy this stuff, so it doesn't bother me. As long as I'm saving a few bucks and it makes my daughter happy, I'm good with it.

Hey thanks for the reply! (And love the thumbnail - lol)

Ok, I'll look for an installer. And to clarify, the PC already came with 4 sticks of RAM -- (2) 1 GB, and (2) <1 GB. So, I was just planning on taking out the <1 GB sticks and replacing them with the (2) 2 GB.

I agree with all the previous advice.

Test the game with Vista 32 Bit and see how it performs with all your hardware upgrades.
You may see you don't need a 64 Bit OS.

Ztruker said:

Post post here:

Vista ISO download

and ask Peter (Ex_Brit) to send you the link to the versions of Vista you need, 32 or 64. Include your E-mail address mucked up, like abc at xyz DOT com then edit your post and remove it as soon as you receive the link.

The ISO Peter provides has both SP1 and SP2 applied.

Pick up the Tutorial: How to Download a Vista ISO and Create an Installation DVD or USB here:

STEP THREE
To Create Vista Installation DVD or USB Flash Drive with ISO File

During the install, when asked for the key, don't enter it. You will then be given a menu where you can chose the version you want to install. Make sure you pick the version that matches the install key you have.

Activate once the install is completed.

HUGE thank you! First, I'm going to see how everything performs with the initial upgrades. Then, I'll see if it's going to be necessary to follow through with the 64-bit upgrade. Thanks again!! (I might just try it out of curiosity!)