Anyway to change the memory ratio in the Dell 5150?

[eBauer]

Have 512MB of DDR2700 in my laptop, however it is only running at a 1:1 ratio. Anyway to run it at 4:5 (166MHz)

CPU is 2.66 P4-M

 

[trungthiendo]

1:1 is usually the best ratio to be running ram and fsb at...why would you change it???

unless you are planning to overclock i don't see any reason to change it so the memory runs faster...

ur computer runs the fastest when ram and fsb are in sync, i'm sure the other members will agree with me on this

 

[mrweirdo]

yes if you try to change it and then get it out of sync it will cause a higher latency thus causing your system to slow down performance wise even though you may think you have made an improvement.

 

[eBauer]

Because DDR2700 memory is in the system and it is only running at DDR2100.

The FSB and Memory ISN'T in sync at the moment (133x4 = 533MHz vs. 266MHz on the memory) - effectively speaking.

Take the i845 chipsets for example. They supported DDR333, but in order to use that memory speed you needed to run a 4:5 memory ratio on a P4B 533MHz FSB chip.

Edit: You are forgetting the P4 has a quad data rate... Even though the FSB is 133MHz actual, it is quad-data rate, hence the 533MHz effective data rate. So we have a 533MHz CPU feeding information only to 266MHz memory. = Not in sync

 

[trungthiendo]

it is in sync...

533= 133x4
and ddr266 is 133x2

therefore both the fsb are at 133...in sync

if you have it running at 333, then one bus will be at 133(cpu) and the other will be at 166(mem)

 

[eBauer]

My goal is to have the memory Memory @ 166 (333 effective)

The way you obtain this on a 533FSB chip is a 4:5 memory ratio. I dont' know why you're arguing running memory at 266 would be better than running it at 333.

 

[trungthiendo]

i'm saying memory ran at 266 in this case would be the better choice because it is actually running at 133 x 2. Which is 266 effectively.

for the pentium 4, the front side bus is 533 effectively meaning that it is 133 x 4.

now do you see how the fsb and the memory speed are same???

this means they are in sync, and running in sync is faster then running other timings.

and no there isn't a way to change memory ratio on dell laptops that i am familar with