Dual Channel much faster?

I will buy a TC4200 Tablet from HP. This Notebook has one 512 MB memorychip DDR2 400 Mhz. Should i buy another 512 MB chip DDR2 400 Mhz or should i sell the installed 512 MB DDR2 400 Mhz memorychip and buy two 512 MB DDR2 533 Mhz memorychips? How much is the Difference between DDR2 400 Mhz DualChannel and DDR2 533 Mhz Dualchannel?

Regards

Matthias

 

Buy another gb of memory. that's what I did.

 

But you haven't DualChannel with this configuration, because both memorychips have to be from the same size.

 

DualChannel is fine, but more RAM is better. DC really won't benefit you as much as it might sound.

 

Basically dual channel works exactly like striping on hard disks. Normally RAM writes sequentially until filled. If writing out two bytes of data both will be written to the first RAM module sequentially. Each byte takes one clock cycle to write so 2 bytes will take two clock cycles. With DDR byte one is written to module one and byte two is written to module two. Both bytes will be written in one clock cycle. As you point out this requires both modules to be of the same type.

While this does effectively double memory write time, other factors tend to reduce the overall system benefit (disk read time, CPU activity, etc.)

Dual channel is a speed improvement over standard RAM. However as Brian points out, if the choice is between 2x512 (1G total) or another 1G chip (1.5G total) I'd skip the dual channel and get the additional RAM.

 

I did not know that it was faster to have two memory sticks of the same size. but let's put it this way. I have 1.5gb of ram. I have about 80 processes running. Firefox accumulates 130000K of memory usage and then it starts to act slow so I reset it. But with 1.5gb I can have 100 processes runnning and as long as they don't overwork my processor to 100% I feel no lag.

 

I'm quite certain that under normal use the perceived speed increase with DDR will be close to zero. However heavy calculations can make a difference. As no Intel chip ever has been endowed with a decent set of registers, applications are left to write out data to RAM a very slow (compared to registers) process. In this case when performing heaving calculations over long periods of time a benefit can be seen. However, if this is your intended purpose I urge you to consider a desktop.

 

can't you do "heavy computations" on a tablet by hand since it is inkable? [/sarcasm]

 

Yes, while listening to "heavy metal" MP3 files. (Give me a break I have two sick kids who will not allow me to sleep, its two in the morning, and I have an early AM conference call. Best I could come up with now)

 

Well tablets don't have very good speakers.