Windows 7 ultimate 64bit on 3GB RAM ?

Hello,
TL;DR ? READ THE TITLE ONLY AND THIS:I'LL BE USING MY PC FOR GAMING.YOU CAN SKIP WHAT I'M GOING TO SAY.

Ok so a couple months ago,I bought windows7 ultimate 64bit...My specs:
Intel Celeron D 3.1Ghz
1.7GB RAM
Nvidia Geforce 7050/nforce 610i 512MB integrated graphics.

But well,it didn't perform as how I expected.It lagged a bit and there was a game(S4League) that I used to play on XP without any problems but it lagged like hell on windows7.So I just installed windowsXP back.

Now,I'm upgrading my PC.Not really a huge upgrade but it would be much better than my current specs :
Intel Pentium Dual Core 3Ghz
3GB RAM
AMD Radeon 6670 1GB GDDR5

I only have 2 RAM slots,1GB on each.So I'm replacing 1 of them with a 2GB RAM card.I don't want to replace the other 1 too,it would be a lose to put 2GB of RAM in my drawer.So I just wanted to know how Win7 would perform with 3GB of RAM.

Thanks in forward.

No! No! No! Put the 2gb of 1gb in your drawer, buy a matched set of 2 x 2gb and enjoy! Otherwise you are leaving yourself wide open to issues where you need to remove the 1gb stick and then get a matched set.

Remember, if you have RAM issues you will be asked:
Is your Ram matched? Same Manufacturer, Type, Model, Size, Batch, Timings, Etc.? Preferably bought as a matched set. Is it on your Motherboards QVL list or is your Motherboard on the RAMs QVL list?

And RAM is that cheap nowadays, why take the gamble??

Oops...Sorry I forgot to mention that my motherboard supports DDR2 RAM only which is more expensive than DDR3 and it can't be found in 2x2 sets.

Edit:I'm ok with WinXP but the problem is I got Battlefield3 which doesn't support windowsXP :/ Well maybe I can somehow run both Win7 and WinXP(dual boot) but won't that slow down my PC ?

My Mobo is DDR2 as well, OK maybe its old hat but I had no problems last year (as in 12 months ago). Why not look for 2 x 4gb? Or just a matching set for your board? With 64bit you won't be disappointed.
If you give full details of your MoBo and your location, I have no doubt you will be swamped with suggestions!

I live in Alexandria,Egypt.
I've asked many times at different shops for 2x2 DDR2 RAM...Best I found was 1 single 2GB RAM.They told me it would be really hard to find more than that when it comes to DDR2.

Well,I searched around to see how win7 would perform on 3GB RAM.I found this thread on Arabhardware forum:
http://arabhardware.net/forum/showthread.php?t=259669

He's running win7 32bit on 2GB DDR2 RAM.And a Phenom II X2 CPU(nearly the same as the CPU I'm getting) and the same video card I'm getting.Its performing pretty well @maxed settings no AA @1280x1024Res(my screen's max is 1366x768).I've read on microsoft's website that win7 64bit needs 2GB RAM to run well.Maybe it didn't run well the 1st time because I got 1.7GB RAM.Anyways,I'll get the card and the CPU and install back win7.I'll see how it performs.If I needed more RAM,I'll get a 2GB card and if I needed even more I'll get another 2GB card.What do you think of that ?

EDIT:wait a minute,I just found out that x86 means 32 bit LOL.My Win7 edition got both 32bit and 64bit...Which 1 should I install when I get my new PC if I'll keep my 2gb RAM for now ? I mean My PC would run pretty well on 32bit but is there any cons. if I installed 64bit instead ?

2GB is the absolute minimum for 64-bit. Unless you ever get more than 3GB of RAM there is not much advantage to 64-bit and it may be a lot harder to find 64-bit drivers with old hardware.

I'd even recommend a minimum of 4GB of RAM to notice any benefits from running a 64 bit architecture as 2GB is a recommended minimum for 32 bit.

Well,I think I'll just install 32bit for now...My RAM is 1984MB,the minimum for 64bit is 2GB.Surely when I get a new video card and disable the integrated graphics it will be 2048MB but that would be kinda bottleneck...So I won't risk it,I'll install 32bit and whenever I get 4GB RAM,the disc will be there...Thanks all

It is best to go with at least 4GB of RAM, preferably as 2-2GB matched sticks. This will enable the Dual Channel DDR2 function.

BE SURE to get good quality RAM, I recommend Mushkin, G.Skill or Corsair, in that order.

Of course DDR2 is more expensive these days! It is the classic law of "Supply and Demand".

Here's two 2GB sticks of G.Skill DDR2 from Newegg for $48.99 plus $.99 shipping! http://www.newegg.com/Product/Produc...82E16820231207

Nibs, I don't think the 99 cent shipping applies to Egypt

Unfortunately, access to affordable computer parts can definitely be difficult in many parts of the world. I agree that 32-bit would be the best for your current situation.