Tom's Hardware > Forum > CPU & Components > CPUs > Final questions on DDR RAM?
Ask the community Add a reply
Word :    Username :           
 
Anonymous   07-09-2001 at 11:27:36 PM

I swear, these are my last questions. Thanks for the patience toward an ignorant (but humble) newbie. People have told me repeatedly that it doesn't matter if the RAM is DDR, it has to do with the processor. However, other people have told me that the motherboard has to support DDR RAM also. What are the differences between motherboards which do and don't support DDR? Second, I have learned that PC133 RAM doesn't neccesarily have to go at 133 Mhz. So, is the 133 just give an indication of the maximum bandwith (in a less obvious way than, say, PC2100 RAM)? Thanks guys. You've been a big help so far.

Add a reply
Sponsored Links
Register or log in to remove.
Stick_e_Mouse   07-09-2001 at 11:54:42 PM
- 0 +

Yes, a motherboard has to support DDR in order to use DDR memory (go figure). It is not backwards compatable with PC133 (a board has to have both pc133 and ddr sockets to support both kinds of memory). Those that don't support ddr support regular pc 133 (or pc100 if they are older boards). Theoretically, DDR is suppose to be a huge performance booster compared to PC133 boards/memory.

<font color=blue>Your mouse moved. WINDOWS NT must restart for changes to take affect. Restart Now?[OK]</font color=blue>

Reply to Stick_e_Mouse
Stick_e_Mouse   07-09-2001 at 11:56:44 PM
- 0 +

and yes, you can underclock the pc 133 ram to 100mhz (or anywhere in between), but performace will suffer greatly.

<font color=blue>Your mouse moved. WINDOWS NT must restart for changes to take affect. Restart Now?[OK]</font color=blue>

Reply to Stick_e_Mouse
FatBurger   07-10-2001 at 12:32:45 AM
- 0 +

The 133 in PC133 is an indication of the maximum rated bus speed. Usually you can go over that, but not always. You can always go up to at least that (or get your money back).

The PC1600, PC2100, PC2400, etc. is the bandwidth. SDRAM and DDR-SDRAM has a 128 bit datapath, meaning it can move data 64 bits at a time, 133 million times a second, divided by 8 (bits to bytes) , equals 2.1GB/s, or PC2100. I hope that helps. Go <A HREF="http://forumz.tomshardware.com/modules.php?name=Forums&file=faq¬found=1&code=1" target="_new">here</A> for my long (and probably slightly inaccurate) definition of busses.

------------------------------
My Athlon can beat your Ferrari off the line.

Reply to FatBurger
Anonymous   07-10-2001 at 02:40:05 AM
- 0 +

So, even if I get an Athlon with a "200 Mhz" FSB, it'll really still only be a 100 Mhz FSB since my motherboard doesn't support DDR? Right? Please tell me I finally understand this.

Reply to Anonymous
agpport   07-10-2001 at 02:52:05 AM
- 0 +

It´ll be a 200 (100x2) MHz FSB, but only between CPU and northbridge chip.

Reply to agpport
FatBurger   07-10-2001 at 05:51:10 PM
- 0 +

Right, it's just your RAM that won't be running at double.

------------------------------
My Athlon can beat your Ferrari off the line.

Reply to FatBurger
Ask the community Add a reply
Tom's Hardware > Forum > CPU & Components > CPUs > Final questions on DDR RAM?
Go to:

There are 1023 identified and unidentified users. To see the list of identified users, Click here.

Forum map
Bestofmedia Forum ©
2000-2009 Bestofmedia Group
Page generated in 0.220 seconds
Please mind

You are about to answer a thread that has been inactive for more than 6 months.
If you still wish to proceed, please ensure that your posting is original and does not duplicate or overlap any prior responses to this thread.

Add a reply Cancel
Sponsored links
  • Ask the community now
  • Publish
Ad
They won a badge
Join us in greeting them
How do I win badges?