Sorry to keep jumping in with controversy, but neither ROM nor RAM are Virtual Memory.
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edit: Mistakes in the post that this one addressed were corrected. (
![bien [img]images/icones/icon7.gif[/img]](./images/smilies/icon7.gif)
good job! ) Unless someone thinks I should delete this post, I'll leave it here for now as a technical reference.
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RAM means "Random Access Memory." When just the term Memory is used, it means RAM.
ROM means "Read Only Memory." Data stored in/on true ROM can not be changed. Firmware is the catch-all term for ROM.
The BIOS and other seldom changing logic is stored in some type of Erasable-Programmable ROM, or a type of Flash Memory.
Cache refers to dedicated or dynamic RAM used for temporary convenient storage, such as CPU Cache, File Header Cache and so forth. Temporary Files in the browser's folder can be referred to as Cache, since the word cache means storage, but they are more specifically just Temporary Files. Cached data is kept for convenience rather than to extend the system's memory.
Virtual Memory is (usually) on disk. It can be thought of as "virtual" RAM, meaning it isn't really RAM but it acts like it. The Windows pagefile.sys is used for virtual memory storage. If a program needs more RAM than is available, the OS will check the things currently in RAM and write the least-active or least-used pages out to disk (memory "blocks" are called pages, and page-size, i.e., how many bytes, depends on the system's architecture). Then, if the program needs that data again something else will be swapped out and the requested pages will be reloaded from the disk.
When a program first loads into memory, it "pages" the program in. If you monitor memory, you will see the "page fault" counter increasing. A page fault means that a program has requested something in memory that isn't there. The operating system "sees" the page fault and services it. An actively running program will show page faults if its pages are being swapped in and out of the pagefile.
Virtual Memory lets a system run more software than it would be able to by using only its RAM. The trade-off is that Virtual Memory on disk is slower than RAM and if RAM is too short the system can spend too much of its time paging things in and out of memory rather than processing data.
I've recommended free cleaning tools like CCleaner and Glary Utilities here before. I have no connection to either but I use at least one of them every day. I'd post a link but I might get into trouble
@Ken: Re-read the PM's we sent each other last year when we discussed Virtual Memory. Use CCleaner or a similar tool to clean up the junk files on your disk and to clean up your registry. Also, if your computer is a little slower-than-newer, right-click the game screen and set the Quality to Medium or Low and see if that helps.