Upgrading memory

[#1]

I have an HP Pavilion Desktop computer which is about five years old now.  It runs Windows XP Home with SP3.  I would ideally like to upgrade the RAM.  It has a 2.66 Celeron processor.
It was delivered with only 512k RAM.  A few years ago, I upgraded to 756k RAM.  There are two slots, one with 512k and one with 256K.  CrucialMemory recommends an upgrade to 2 Mb.
I thought that I would check with HP before I ordered, and this is the reply which I got from HP :

Quote

The motherboard has two dual in-line memory module (DIMM) sockets. Minimum memory module size is 64 MB; maximum memory module size is 512 MB. The BIOS automatically detects memory type, size, and speed. The motherboard supports the following memory features: 184-pin DDR-DIMMs PC2100 and PC2700 DDR-SDRAM non-ECC (64-bit) DIMMS 2.5 V memory only 1.0 GB maximum memory      Note: The maximum memory figures quoted for each motherboard are based on the most current maximum HP-approved memory capacity for each motherboard. While many of the motherboards' chipsets may support higher maximum memory, HP does not recognize maximum memory figures in excess of the approved limit.

That has taken me by surprise.  I do not understand why the motherboard should be limited like this, but perhaps someone else knows the answer.  Clearly, I do not want to waste money on buying new RAM which will either not fit or not work.
Does anyone have any experience of this or could anyone recommend what to do ?
Many thanks.

[#2]

Im not sure why the memory is limited on desktop pc's,however i know mines can go no more than 2gb and im using an old dell optiplex gx260,you should be fine getting a nother 512mb as that would take you too your limits,presuming you used crucials tool then you should be good with what they suggest,i upgraded from 512mb ram to 1gb ram from crucial with no problems,dont notice much difference though if im honest.
PS did they really recommend 2mb? dont you mean two GB? i would buy a 512 and replace the 256 one and see how that goes

[#3]

If you've only got 756k memory I'm surprised your machine runs at all (my first 286 based computer had more than that!).
I think you mean 756Mb!
When you've got a typical set of programs open go in to Windows task manager. On the performance tab look at the Commit Charge Total. If that is more than your current 756Mb adding more memory will make a difference. Going to more memory than the Peak value is unlikely to make a lot of difference.
I've got a GX270 with four slots, currently 2x256Mb and 1x512Mb (1GB total) current Commit Charge Total 1024152. Hopefully tomorrow another 512Mb module is arriving from eBuyer - with a bit of luck that should make a difference for me.

[#4]

Go with the Crucial recommendation and buy direct from them as they give a no quibble money back guarantee if it doesn't work

[#5]

If the Peak usage never goes over 1GB why go for more than 1GB memory? - save the money towards a new PC!

[#6]

Thanks guys
The I need to monitor the Commit Charge which I will now do.  Currently it is just below my 756Mb (sorry, I did mean of course Mb not K !).  My main complaint is that it takes forever to boot up and the hard disk goes on "chattering" for maybe ten minutes - I assume it is committing data to the Virtual Memory all this time, which is why I thought adding memory might help.
In fairness, I have no complaints about the speed of response generally after things have settled down.  Going to 1 Gb may be a good half-way house, which is what HP recommends of course.

[#7]

Before you go and buy yourself the added ram why not go to the task manager by pressing control,alt,and delete then go to the processes and see what you have running?Also maybe your pc just needs a good spring clean, disk needing a defrag or maybe your registry could do with a clean,you could try ccleaner,its a free programme you can use and a lot of people use it,it cleans really well.

[#8]

This is also a pretty good memory configurator - and a low price site:
http://www.7dayshop.com/daneelec/index.php

[#9]

I had similar problems and upgraded my Dell Optiplex from 512mb to 2GB which helped a great deal but I also found that using TuneUp
really helped as it not only cleans up the registry but also does other useful things.
It's free for 30 days which is long enough to solve all your problems.
I've had it running on 3 of my PCs and a laptop.
http://download.cnet.com/TuneUp-Utilities-2010/3000-18512_4-10206416.html

[#10]

Steve has a point. Have recently worked on 2 HP Pavilions and both are now twice as fast. Admittedly, had to reformat them though.
If you are not wanting to do this, I would definitely look at what's running in task manager and what you can safely shut down.
Uninstall what you don't need, give it a good clean up with CCleaner and a defrag wouldn't come amiss too.
Might be worth taking everything out of start up that's not needed. 
Memory is expensive and if you can't improve performance with house-keeping then it might be better to save the money and put it towards another computer.
The HP would work very well as a second computer running Linux if you are so inclined.

[#11]

Quote from: poppy

Memory is expensive

Not really, it depends what generation it is.
DDR2 is dirt cheap these days.
DDR (e.g. PC2700/PC3200) which is more likely for that "vintage" isn't too bad, say £30 for 1GB new.
For an older PC you could look at buying used on eBay and save some money.
TBH 768MB should really be enough though 1GB is maybe better, depending what you use the PC for.
I'd just replace the 256MB stick with 512MB and look at what's running too.
Maybe something "unwanted" or malicious is in there?

[#12]

Quote from: shermans

...It was delivered with only 512k RAM.  A few years ago, I upgraded to 756k RAM.  There are two slots, one with 512k and one with 256K.  CrucialMemory recommends an upgrade to 2 Mb....

Crucial have a vested interest in selling you memory so I would not trust their recommendation.  Windows XP was developed when memory was much more expensive than now.  The cheaper systems were originally sold with 128 MBytes of RAM, 256 MB was the norm and 512 MB would have been pretty luxurious.  Since then some programs, notably the commonly-used security software, have become more hungry for RAM so you do need more.  But you are up against a law of diminishing returns and I doubt you would see much improvement in performance adding memory over 1 MByte (if you could).  Nor do I expect you would see much difference if you replaced your 256 M module with 512 M.  If you want to improve performance, get rid of your Norton security software and replace it with something that has less of an adverse impact.     

[#13]

Quote from: ReedRichards

get rid of your Norton security software

Where was that mentioned? 
(And yes, I'd probably replace it if it was there and taking ages to load)

[#14]

Yes, yes, nobody mentioned Norton security software; just an educated guess.

[#15]

Personally I would recommend at least 1GB for using with XP, but it does sound as if its needing a good spring clean.
If you are using norton it would be worthwhile seeing if your version allows you an upgrade to the latest version free, as its a lot lighter on resources and with recent testing I have been doing here I am finding a lot better and even convincing me to possibly switch from kaspersky which has been nothing but problems (although the latest build on windows 7 has been a lot better).