I often get a message that there is too little (virtual) memory, and all processing slows down. HP says that the RAM should be labled as Compaq, or it may not 'work'. The 256Mb of RAM that 'work' are NOT 'Compaq' labled. HP do not stock 256Mb SODIMMs for the E500. I bought two 256Mb SODIMMs on Ebay. Their chips are marked SAMSUNG. The laptop either does not boot, or ignores the 256Mb increment in any of the many combinations in which I can introduce one (or both) 256Mb SODIMMs. Is there a solution to upgrade the RAM to the allowable maximum of 528Mb ? There is a second phenomenon : that sometimes it boots to a window saying there has has been a change in RAM (halved). Typically at the next boot-up, a reverse message will say that the RAM has changed (doubled). Basty

"I often get a message that there is too little (virtual) memory" Are you running low on HDD space? "And that's the fishing line, because Sharkboy said so!"

You may have TWO different issues going on. Virtual memory involves harddrive space. Laptops are very fussy about the RAM you install. You have evidently installed incompatible RAM. Only buy RAM that has been certified to run on your system. You don't necessarily need to buy RAM from HP but that would be one example of certified RAM. Look at any of the major RAM vendors and they should have system specific RAM modules. You still must go by the manual too.

"Virtual memory involves harddrive space." and, if you only get the message sometimes, on how much virtual memory is required to run all the programs you have loaded , and/or load all the things you have loaded other than programs, at that time when you get the message. If you don't have enough free space on your C logical drive partition in proportion to the total size of the partition, you are likely to get messages about there not being enough virtual memory. Sometimes you can do things to reduce the number of times you get the message - e.g. if you have opened a lot of images, they take up virtual memory even if you have minimized them - close some of them. The solution is often to free up some hard drive space by deleting or un-installing things you are not using (never delete what you can un-install), or to copy data elsewhere such as to CDs or DVDs and delete the original files. .... Ram that works in another mboard , or any ram you buy or have lying around, may not work properly, or sometimes, not at all - even if it physically fits and is the right overall type (e.g. SDram, DDR, DDR2, etc.; PCxxxx, xxx mhz) for your mboard. In the worst cases of incompatibilty your mboard WILL NOT BOOT with it installed, and the mboard may not even beep - the ram has to be compatible with the mboard and it's chipset. See response 5 in this for some info about ram compatibilty, and some places where you can find out what will work in your mboard for sure: http://www.computing.net/hardware/w... Correction to that: Mushkin www.mushkin.com "HP says that the RAM should be labled as Compaq, or it may not 'work'." Even that doesn't guarantee it will work, unless it has a HP or Compaq part number that is compatible with your model, or with similar models with the same main chipset. "The 256Mb of RAM that 'work' are NOT 'Compaq' labled." System builders specify particular part numbers of ram you can use, and they may also specify an oddball ID string that only they use. They don't make the ram - the ram is supplied to them by major manufacturers and there are usually many other computers that can use the same ram, but not all other similar computers can. The ram manufacturer's ID string is often underneath the stuck on part number label on ram supplied by the system builder, if it isn't an oddball one. When you find and look at lists of ram that work in your system model, sometimes the ram ID strings are only the oddball ones specified by the system builder (this happens more often in the case of laptops), or the list may have normal ram manufacturer's ID strings, that are used in all sorts of computers, for the ram. If only the oddball ID strings are listed, that usually doesn't mean only that ram will work - any ram that is meant to be used with your main chipset, or in the case of recent AM2 or AM2+ computers with the memory controller built into the cpu, and is physically compatible with your ram sockets will work fine. "There is a second phenomenon : that sometimes it boots to a window saying there has has been a change in RAM (halved). Typically at the next boot-up, a reverse message will say that the RAM has changed (doubled)." A common thing that can happen with ram, even ram that worked fine previously, is the ram has, or has developed, a poor connection in it's slot(s). This usually happens a long time after the ram was installed, but it can happen with new ram, or after moving the computer case from one place to another, and I've had even new modules that needed to have their contacts cleaned. See response 2 in this - try cleaning the contacts on the ram modules, and making sure the modules are properly seated: http://www.computing.net/hardware/w... For a laptop, you must remove both its main battery and AC adapter before you do that. If you do a ram test, do that AFTER having tried cleaning the contacts and making sure the ram is seated properly - otherwise any errors found may be FALSE. If the ram is incompatible with the chipset, it will likely FAIL a ram test - that is NOT a true indication of the ram being faulty - there is probably nothing wrong with it, and it will pass the test if installed in a mboard it is compatible with. If you want to try a memory disgnostic utility that takes a lot less time to run a full pass than memtest86 does, this one is pretty good - Microsoft's Windows Memory Diagnostic: http://oca.microsoft.com/en/windiag... It can be toggled to do a standard or a more comprehensive set of tests - use the latter one. A few of the tests are intentionally slower.