Whats the speed of my RAM?

[go4saket]

Hi Guys!

I have a P4 with 512 MB DDR RAM. As to what I remember, I took a 400 MHz. RAM but when I check the same with CPUZ, it shows both 166 MHz & 200 MHz. Even if I add it, it comes to 366 MHz. How is it actually calculated?



Thank you.

[infra_red_dude]

Thats DDR = 2 x Speed. So 2 x 200mhz = 400mhz.

[Beta Waves]

Internal clock in DDR2 will be half of what the actual transfer rate is ... Coz in DDR2 there will be two data transfers in every cycle

But in your screenshot it is showing DDR and not DDR 2 ... So it may be 200 Mhz itself ..

If you want accurate value check in BIOS

[go4saket]

DDR doesnt come in 200 MHz. Its comes in 266, 366 & 400 MHz, if I am not wrong.

[infra_red_dude]

Originally Posted by Beta Waves

Internal clock in DDR2 will be half of what the actual transfer rate is ... Coz in DDR2 there will be two data transfers in every cycle

But in your screenshot it is showing DDR and not DDR 2 ... So it may be 200 Mhz itself ..

If you want accurate value check in BIOS

Where has he said that he has DDR2?

Originally Posted by go4saket

DDR doesnt come in 200 MHz. Its comes in 266, 366 & 400 MHz, if I am not wrong.

I really dunno what the confusion is all about. What you've paid is what you've got!

DDR = Double Data Rate = 2 x Rated Speed, hence DDR400 = 2 x 200mhz.

Plus, do you see the rating there? PC3200? The 3200 represents the bandwidth in MB/s.

How do you calculate this? DDR Ram has a 64bit wide channel.

BW of DDR RAM = 2 x Rated speed x 64bits x 8bits/byte

Hence 2 x 200mhz x 64bits x 8bits/byte = 3200 = PC3200. The highest DDR ever produced was DDR400 which has a bandwidth of PC3200. Since your module has the exact same bandwidth (PC3200), your RAM is DDR400. There is ABSOLUTELY no doubt about it.

Rest assured

[Beta Waves]

Sorry I made a mistake in my previous post ...

DDR RAM internal clock wil be half the rated speed i.e yours is DDR 400 that means internal clock is 200 MHz .. so it is showing correct ..

DDR2 RAM internal clock will be 1/4 the rated speed ..

[go4saket]

Thanks a lot guys! Confusion cleared...