Dual Channel vs Single Channel

Question Would it be better to run 2x512MB pc4200 dual channel or 1x1gb and 1x512mb single channel?

 

As long as they are operating in dual channel 2x512 as it will double the bandwidth of your memory bus

 

I note you are asking about running 1Gb in dual channel or 1.5Gb in single channel, wondering which is better? Less RAM in a faster configuration or more RAM that runs slower. And in that case, my answer is, "it depends".

It depends on your operating system. It depends on the programs you are running. And it depends on the specific task or tasks you are asking of your computer.

NO DOUBT running in dual-channel mode is typically preferred because, as Tueur noted, it effectively doubles the bandwidth - and that is great. But in this case, we are still only talking about 1Gb of RAM and that is not very much at all - not today when not only do you need a nice chunk of RAM for the OS, but you also need lots of RAM for the essential security tools you must run - thanks to badguys - just to be safe. At the very least, you must run an able anti-malware solution and firewall application and that leaves little room for your browser, word processor, email program and other things you normally run.

And if this is a notebook or PC with an integrated graphics solution, then a big chunk of that 1Gb right up front has been stolen... err, I mean is being dedicated as "shared" memory for graphics.

When you run out of system RAM, as you quickly do with only 1Gb of RAM, Windows and your CPU have no choice but to shuffle data back and forth to the Page File on the very slooooooow (compared to RAM) hard drive. And single channel RAM is MUCH faster than the fastest hard drives. So if your system (to include the programs you normally run and/or start with Windows) needs more than 1Gb of memory for decent performance, then running with 1.5Gb, even in single-channel mode, may prove to be better for you - especially if some of that RAM is being by graphics.

Try it both ways and see for yourself. Just make sure you unplug from the wall and touch bare metal of the case interior BEFORE reaching inside the case to ensure no destructive static is in your body, and that you never touch the electrical contacts of the RAM modules.

That said, my recommendation is to buy another stick of 1Gb, or better yet, a new pair of 1Gb sticks (RAM is cheap and buying in pairs ensures compatibility) and bump your computer up to 2Gb with 2 x 1Gb running in dual channel. Your CPU, Windows, and your hard drive will love you for it - and you will likely see a nice all around performance bump too - ESPECIALLY is running with integrated graphics. If your motherboard supports 2Gb sticks (or has 4 slots), I recommend going up to 4Gb. The price difference from 2 to 4 is worth it - but again, only if your board supports it.

Remember, when it comes to improving overall computer performance, the general rule is you get the most bang for your money by first insuring you have lots of RAM for your OS and Windows to play in. This is particularly true for systems starting out with low amounts of RAM.

Yes, you end up with sticks of perfectly good RAM not being used. Welcome to the club. I have a whole drawer full of old RAM, and shelves full of perfectly good, but old hard drives, motherboards, CD drives, sound cards, graphics cards, PSUs, CRT monitors, etc.