Virtual memory

[#1]

Quote from: Peter

I would never recommend anyone running XP SP3 to have less than 1GB of ram for anything like usable performance.

Here we go again.  It seems to me there is quite a difference between what one might recommend for good performance and telling someone to spend money to buy extra memory that might be better added to the New Computer fund.  I'll just say again that I see many computers that run Windows XP perfectly well with 512 MB of memory.  Sure, they would run better with 1 GB but it really isn't a necessity.  So for me it's:
"I would never recommend anyone running Windows XP to have less than 512 MB of RAM".

[#2]

I'd agree that 1GB isn't the minimum - it really depends upon what software you've put on the PC, whether that software has installed anything that loads at startup and how much memory the programs you want to run are going to use. I have a piece of software that I need to use daily that won't run under Win 7 so I have a Windows Virtual PC running XP. I've allocated it 512MB memory, but I'm thinking of reducing it to free up more memory for Win 7. Why? Because with the application loaded the Commit Charge is currently showing 332740 (and available memory is showing 253192) so it doesn't need all of the 512MB. However startup of the application uses more and the peak Commit Charge is showing 591332 so I have to balance slower startup against more memory for Win 7.
On the other hand I've had a previous XP PC where it had 1GB and was slow and doubling the memory was like getting a brand new PC.
Just saying slow PC - stick in more memory is absolute tosh if you don't check if it needs more memory first. First question, when you are using the PC (and particularly if you swap from one application to another) does the disk rattle a lot? If it does that's one sign that more memory might be needed. Second check - as I described above look at the memory usage.

[#3]

Quote from: ReedRichards

Are the Service Packs and updates more demanding of memory than the original XP software they replace?

Absolutely, hugely so.  
In well over 10 years a massive amount of functionality and "better" (more secure) but larger code has been added to XP.
And of course the applications you run on it.  
It depends how you cost and value your time, but unless it's extremely cheap (well under £1 an hour) adding extra ram is the most cost-effective solution by far.
As jelv says, you need to ascertain that first, but with 512MB it's VERY likely. 

[#4]

If you are unfortunate enough to be running Windows on a motherboard that can't take more than 512MB due to legacy hardware limitations, what I recommend is to add a small second hard disk drive (preferably 7200rpm with at least an 8MB buffer - <£10 of eBay), and then configure the Windows swap file to be located on this second physical drive and be fixed at the maximum size that it will allow you to set.  That way when Windows is going mental swapping pages in and out, because the swap file is on a different drive spindle, the seek and access times are dramatically reduced because the movement of the drive head is not being shared with all the other unnecessary accesses that Windows does on the original drive.
While not as much improvement as being able to fit more enough RAM, it still makes a worthwhile difference, and can make an old frustratingly slow machine become usable again.

[#5]

Thx for all reply's guys,in the end i had to get another tower as it was getting unusable with mouse freezing and browser crashing all time,but the same does happen with my new one now and its running same specs windows xp and 512 of ram and has virtually nothing on it,it will make do for time being while i build a new tower with much higher specs.