Overclock.net › Forums › Components › Memory › Confused about dividers
New Posts  All Forums:Forum Nav:

Confused about dividers

post #1 of 4
Thread Starter 
I've read that its best for a 1:1 FSB:RAM ratio, so why do people implement dividers?

I really need help on this, because my parts are coming in soon and i need to know what i should implement (ie a Q6600 G0 and 4gb DDR2-800 Ballistix)
post #2 of 4
those dividers are there so that FSB and RAM speeds can be different, because the RAM might not be able to handle the FSB speeds otherwise, or because the RAM can go further than the FSB. 1:1 (for example: 333FSB / 333RAM -> 1333QDR / 667DDR) is generally the best, but 1:2 (333FSB / 667RAM -> 1333QDR / 1333 DDR) is perfect. nowadays, 2:1 is used for DDR1, 1:1 for DDR2, and 1:2 could be done with DDR3.
other dividers, like 2:3 (400FSB / 600RAM -> 1600QDR / 1200DDR) are sometimes used to push the RAM to its limits, while keeping FSB within limits and OC with CPU multiplier instead. in the mentioned example, this provides better performance, as the MHz increase of the RAM outweighs the advantages of 1:1. (if the NB and RAM can exchange data at the same speeds, there arent any wait-periods. if the NB and RAM run at different speeds, the fastest of the 2 has to wait for the other to accept the data, due to this 1:1 outperforms 4:5 or 5:6, even though the latter 2 have higher memory speeds)

so in your case, as you have DD2-800, 2:3 would give you memory speeds high enough to outweigh the 1:1, but real life performance (games) doesnt notice the difference, so i advice 1:1. this keeps your RAM a little safer.
post #3 of 4
Quote:
Originally Posted by CantSayThat View Post
I've read that its best for a 1:1 FSB:RAM ratio, so why do people implement dividers?

I really need help on this, because my parts are coming in soon and i need to know what i should implement (ie a Q6600 G0 and 4gb DDR2-800 Ballistix)
A 1:1 divider is simply not the ideal setting. In reality, a 2:1 (Memory:FSB) would net you the most bandwidth. There is no performance loss when running a divider. A high memory speed will always be faster.

So just run your FSB and memory at the highest speed they can run. The whole thing about dividers is just a way of comparing the FSB and memory speed in relation to each other.
System
(13 items)
 
  
CPUMotherboardGraphicsRAM
Core i7 2500k ASRock P67 Extreme4 Gen 3 AMD 7970 16GB DDR3 
Hard DriveOptical DriveOSMonitor
Intel 520 256GB SATA DVD Burner Windows 7 64 bit Deal U2410 
KeyboardPowerMouse
Adesso Mechanical Silverstone OP650 Logitech G700 
  hide details  
Reply
System
(13 items)
 
  
CPUMotherboardGraphicsRAM
Core i7 2500k ASRock P67 Extreme4 Gen 3 AMD 7970 16GB DDR3 
Hard DriveOptical DriveOSMonitor
Intel 520 256GB SATA DVD Burner Windows 7 64 bit Deal U2410 
KeyboardPowerMouse
Adesso Mechanical Silverstone OP650 Logitech G700 
  hide details  
Reply
post #4 of 4
I still say the divider doesn't matter. the highest you can get for fsb and ram is the best
so like lets take for instance your board maxes out at 400mhz (1600mhz rated FSB (just a for instance) but your ram chances are can clock out to higher then that to 500mhz (1000mhz rated) then you would run a 4/5 divider so your ram would run at it's peak. this will give better performance to max everything out as far as it would go.
compy jr
(13 items)
 
  
CPUMotherboardGraphicsHard Drive
xeon 3350 at 3.6ghz Asus P5k-dlx HIS 7970 @ 1150/1900 Lots of them.  
OSMonitorKeyboardPower
vista ultimate x64/xp sp3 compaq 21" junk dell keyboard corsair tx850m 
CaseMouseMouse Pad
upgraded metal box You don't need a mouse Desk 
  hide details  
Reply
compy jr
(13 items)
 
  
CPUMotherboardGraphicsHard Drive
xeon 3350 at 3.6ghz Asus P5k-dlx HIS 7970 @ 1150/1900 Lots of them.  
OSMonitorKeyboardPower
vista ultimate x64/xp sp3 compaq 21" junk dell keyboard corsair tx850m 
CaseMouseMouse Pad
upgraded metal box You don't need a mouse Desk 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Memory
Overclock.net › Forums › Components › Memory › Confused about dividers