PC4200 vs PC5300?

I'm looking into upgrading the RAM for my laptop, and I'm not clear about what the difference is between PC4200 and PC5300 (assuming that you're dealing with the same size stick of RAM)? I'm specifically trying to figure out:

1. Is one type faster than the other?

2. Will one type run cooler than the other? This is my main concern because I don't have a high quality laptop.

Thanks.

 

RAM speed is only important and necessary if your laptop actually runs it at the higher speed. Which notebook do you have and what are the specifications? Most notebook platforms only support one kind of RAM, so getting the higher end would be a complete waste as it will run the new RAM downclocked to the lower speed. For example if your system is running at memory at 266Mhz, getting PC5300 ram will not mean your system will be upgraded to 333Mhz, rather the BIOS of the notebook will downclock your new ram to 266Mhz.

1. Yes, PC5300 is faster than the PC4200. PC5300 runs at 333Mhz(DDR667), whereas the PC4200 runs at 266Mhz(DDR533). These are the DRAM frequencies from the system level. Of course DDR means "Double Data Rated", which often lead to very confusing numbers of 667 and 533 respectively.

2. Possibly, but there will be no noticeable temperature difference as it would be negligible between the 2 types of RAM.

 

PC4200 is 533Mhz, 533X8=4264, PC667Mhz, 667X8=5336. Do you see how they got there names? Oh and those numbers are MB's, 4200MB/s and 5300MB/s the maximum theoretical bandwidth of those two speeds. Neither of these get anywhere close to these theoretical numbers. One reason is FSB speeds. On notebooks I think fair to say between 3000MB/s and 3500MB/s. And the faster RAM not always higher throughput on different systems. For example I have AMD w/1600Mhz FSB I get about 3300MB/s w/533Mhz. Almost as much as people with Intel 667Mhz and 800Mhz FSB, I do better than people w/Intel and 533Mhz or 667Mhz FSB and 667Mhz RAM.

With these two speeds it is not a straight equation. The 667Mhz is 27% faster speed wise but it has a higher latency 5 vs 4 so the 667Mhz has a 25% higher latency. If your notebook supports 667Mhz use it a little faster but not much.

Heat is not an issue. And remember to get the higher speed your computer has to support it, you can't just pick faster RAM as system controls how fast it can work. 667Mhz RAM in a system that supports 533Mhz will run at 533Mhz.

 

AMD... with FSB?

Anyway, check if your notebook is compatible with DDR2-667 MHz memory. If it is, then by all means get PC5300 RAM.

 

Thanks for all of the input. I have an Acer Aspire 9410z (that is it aspires to be a decent laptop, but isn't). It's got 1GB of RAM running the RAM hog of all operating systems. Since RAM is fairly cheap these days, I've been looking to upgrade to 3GB. I did some research, and my system supports PC5300 and PC4200 memory.

Thanks for explaining the difference, and how they come up with the numbers, that will be really helpful.