[quote=“Chicken”]For photoshop it might help you manipulate large files to add in more memory. But it is called DUAL data rate for a reason. It works better with 2.
If you can find a cheep (used is ok) stick of 1 gig then go for it, but right now the old memory is at a premium price.
If you need to keep this computer for a year or more then I would put in the 2x1gig stickes. Memory is the best thing you can add. Whats your MoBo? I could look it up and give you better advice if you know it. And CPU. Also take a look inside and make sure you don’t have 4 ram slots. If you do getting 2x512 would be great (in most Mobo’s). I could even sell it to you as I have some sitting here. I could slap it in if you are near Jiayi.[/quote]
[nerdtalk]
I think your mixing up two different things here.
One is DDR (Double Data Rate) SDRAM which is a type of memory, as it’s name suggests, offers double the bandwidth compared to it’s predecessor SDRAM. This is achieved by sending data twice per clock pulse, (imagine the form of a digital pulse) once every time the pulse reaches a peak and another when it reaches a valley.
The other is a technique of addressing two memory modules in a way to double bandwidth called Dual Channel.
For example we have a 2 X 512MB setup. Traditionally a memory module is being filled and addressed one at a time, when the first module reaches it’s capacity of 512MB then the 2nd module is being addressed (effectively just using a single channel to the memory).
But what Dual Channel does is it addresses the the two memory modules at the same time hence called Dual Channel which results in an increase of bandwidth. Note: I said increase of bandwidth and not doubling it because of the complexity of keeping track of it all creates some overhead, thats also the reason why we don’t (yet?) see triple or quad channel implementations out there I think.
Anyway there are some requirements and restrictions for using Dual Channel though, one of them is you obviously need two memory modules of the same capacity and the other is your mobo needs to support it. Another side note: while using two identical memory modules is highly recommended you don’t need to pay premium price for a “matching pair” or “specially engineered for dual channel” memory, any two identical modules will do. Thats just marketing at work to get ignorant consumers to pay more for the same thing.
[/nerdtalk]
Anyhow as for the topic starters question: I think upgrading to 1.5GB will do as a temp solution since that will reduce the HD swapping. Accessing your RAM instead of your HD does make an HUGE difference, your HD will have a throughput something like 100MB/s and access time of 9.3ms (9300ns) while a DDR333 will be around 2700MB/s access time 7ns (so RAMs bandwidth is 2700/100= 27 times greater and 9300/7=1328,5 times less latency). While looking for a slab 1GB DDR mem you can also buy a 400MHZ (pc3200) module since the price difference is nearly nonexistent, the 400MHZ module will then simply run at 333MHZ speed like the rest of your memory.
Yes it is basically plug and play, if you know where/how to plug it, and no you don’t need to change any BIOS settings. I’ve heard of some horror stories where people managed to brute force insert the RAM module the wrong way around, turn on their pc and then wondering why it’s not working and why there is a smell like something is burning 
As for choice of brands just avoid the no-name crap and spend a few more bucks for a well known memory brand like Samsung, Kingston, Micron, Hynix ect. just to avoid the possibility of an instable system or even worse data corruption and wasting a whole afternoon because of it (speaking of personal experience here). There usually is a list, on the mobo manufacturers website or manual, of memory which has been tested by the manufacturer if you want to play it safe.
And finally defragging your HD might also help a little bit for the times when the HD needs to be accessed anyway.
p.s. For some odd reason I always get the urge for some Flemish pastries every time I see a post of belgian pie :hungry:
but look at how long it took him to explain it.