I'm upgrading my system, Pentium 4 3.2HT, 1024Mb RAM, 128Mb Radeon 9800 Pro video. I've already ordered the upgrade to the video card (GeForce 7600GT AGP), and am ready to add more RAM specifically to improve performace of FS9 and many FS add-ons. I obviously have no immediate plans to migrate to FSX since I'm upgrading a current computer rather than buying a new one. My question is how much RAM should I add. I read that WinXP itself uses about 512Mb of RAM - so if I add another 1024 (2Gb total), will that be enough - or should I spend the extra $$ and go to 3Gb? Or is that overkill for FS9? Please, for those knowledgeable in such things, what are your thoughts since I'm ready to move on this?

I've heard more than one here say that 2 is about it, as far as FS9 goes, when combined with a good processor and vid card. I plan to up mine to 2GB here shortly.

I have a program running in the background whenever I use FS9. The program periodically optimises the RAM. It includes a graphical display of how much RAM is being used. When FS9 is running, this never goes above about 800MB in total (i.e. FS9 plus the OS plus anything else I have running never uses more than 800MB in total).Which suggests that 1GB is plenty.Martin

Put in 2GB of RAM, definitely! It is well worth it, especially if you want to fly a PMDG aircraft or use photo realistic scenery. You can only put in 2GB maximum of RAM with Windows XP by the way, so there is a limit.Kim

Martin,Would you mind letting me know what program you're using to optimize the RAM? Is it MemTurbo? Thanks.

Whilst FS9 will function well with 1GB, 2GB is good if you want to run a few addons and external programs at the same time as FS9. 3GB is definitely overkill for FS9.Gary

2GB is superb; 3GB is overkill and you'll never need it.Reckon on about 350-400MB to operate Windows XP and your other junk in the background, PLUS 350-400MB for default FS2004( with Cessna), rising to approximately 1GB or possibly 1.2GB for something complex like the PMDG 747-400. So you'll always have several hundred MB or RAM unused which is about what you want.I recently upgraded my DELL XPS Gen 4 from a factory fitted 1GB to 2GB and upped the card from a Radeon X850XT PE to an eVGA 7900 GT (512 RAM) and am extremely satsified with the results. The processor is a 3.80Ghz P4. Loading times were cut in half, frames are steady and stable, fluidity is good, temps are low (never over 54C and often well below) and it's been worth every nickel. I recently added another monitor so I have a TH2G set-up. It's better than going to the movies. I'm glad I didn't go for 3GB RAM, it would've been a waste.I don't have FSX and have no plans to migrate for at least a year or more, if ever. When I do, if I do, I shall get a new rig that is at least twice as powerful but since that will cost another arm and a leg, it's not even over the horizon yet.JS

Chuck,It's called Wincleaner. There has been at least one thread in the FSX forum discussing it. It's supposed to help with frame rates. But it also reports on memory usage.Martin

Thanks everyone for your thoughts. I've ordered an extra GB of RAM taking it 2GB. That, plus the upgraded video card, should go a long way to keeping me satisfied with FS9. There's just something about FSX that doesn't thrill me - I don't know if it's the need for a new computer that won't necessarily provide superior performace, or what. In any event - FS9 is quite ample for the time being.

2GB for FS9....just fine, that's what I run