I've found that the RAM usage is more related to the number of charts and the software used to generate the charts, rather than the number of monitors. For instance, when using TWS charts, the very inefficient Java program used to create the charts uses excessive amounts of RAM for each chart, while better charting software such as Ninjatrader would use substantially less RAM for the same number of charts.
If it is all usable, even just for operating system, that is good enough. At least my PC will work faster, right? Can Windows 7 32 bits Home Premium also use 4GB ram? I have both XP and Win7. I installed 4GB ram, but it shows 2.75GB is usable. Does it mean that the operating system still can use 4GB?
If the OS "used 4GB", there wouldn't be any left to run your applications. All you need to be concerned about is whether the 2.75 GB of RAM available is sufficient to run your applications. Check your Task Manager when all of your trading setup is running.. see how much physical RAM is being used.. probably < 1GB. So long as your setup isn't pressing the 2.75 GB limit such that the OS is paging out a lot, then your RAM situation is functionally as optimal as it can be. If you want to up the 2.75GB to 3.25 or 3.5 GB, try running video cards with less memory on them, but RAM helps you only when it's being used. Having more and more RAM... but it sits idle waiting for something to do... doesn't speed up your computer.
LOTS of people increased their XP rig's RAM from 1 GB to 2 or 4GB... only to see virtually zero performance increase.
I ve just checked Task Manager, it shows that I am using 42% of physical RAM...does it mean I am using 42% of 4GBRAM?
Is that on a W7 rig? I don't see a percent of RAM use calculation on my XP Task manager. The quick reference is in the lower right corner... "Commit Charge"... you'll see a number like "698M/2635M" (that's what mine's reading right now. That means I'm currently using 698 MB of RAM out of a possible available 2.653 GB"... I'm currently using 26% of the RAM which the system makes available to run applications. (The balance of my 4GB RAM is "reserved" by XP for system functions.. including video card addressing.) If you are using only 42% of physical RAM, adding more won't speed up your system... the extra you add will just sit idle and be a waste of money. Of course, you might run some video editing program at some time... those tend to use more RAM.
Why does it show the usable RAM is 2GB RAM when I just add 2GB RAM. Why Windows XP doesn't reserve any RAM from this 2GB RAM for system use?
Lots of W7 systems are being sold with 4-6GB of RAM. If you are using only 42% now, check later in the day and see if that percentage is quite a big higher to evaluate whether adding more RAM might help. When XP came out, RAM was expensive. XP was designed to "page out" lowly used and lower priority functions to the "page file" (on the hard drive).. to keep more physical RAM available at all times in case it's needed. In the time of W7, RAM is cheap. W7 is written to "cache everything", more or less... to make files previously accessed in the session more readily available if accessed again. Therefore and relative to XP, W7 can build up a lot of RAM usage over a day-long session. 4-6GB of RAM in W7 is enough for most users. But if you do add RAM, you should do so in a configuration supported by your mobo. (An x58 mobo would like either 6 or 12GB of RAM, but not between. A P55 mobo would like multiples of 4... up to the mobo's max.)
I don't know the answer to that. Perhaps XP just grabs RAM as needed, coordinated with the page file. But when you install 4GB of RAM, XP "permanently" blocks off some of it for system use.