SUBSIM Radio Room Forums - View Single Post - I'm considering to upgrade mu CPU. Need advice

Arclight · 04-01-09, 12:41 PM

About matching the RAM & CPU: I've got my memory at 1066, CPU at 1333. I don't think a CPU at 1066 FSB would be better. Yes everything would be running in sync, but I sincerely doubt it would make up for it.

Uhm... now that I think about it: true bus speed for Intel CPU at 800MHZ=200MHZ; FSB gets "quad-pumped" to 800

True speed for DDR2 at 800MHZ=400MHZ; it gets "double-pumped"

I think that if you go into the BIOS and look up the divider, you'll find it's set to "2", not "1" (which would be synced).

(all this is making my head hurt, and I'm not even 100% sure...)

In my case FSB is slightly overclocked at 355MHZ (initial 333). This gives 1420MHZ external bus for CPU, and 2.84GHZ clock speed.

For RAM it gives 533MHZ bus speed, 1066MHZ clockspeed. RAM ratio=3/2 (meaning RAM bus is at 150% of CPU bus).

(ouch)

In short; I don't think you're system is running synced as it is. The RAM is running on considerably higher bus speed, so moving to a CPU with higher bus speed will only do you good.

Please, if anyone has more insight in this feel free to correct any of this. It's hard to keep track of all this stuff.

*edit: if you want to check you can download CPU-Z; start the program and look under the "memory" tab and see what the FSB to RAM ratio is. It should read "1:1".

04-01-09, 12:41 PM	#7
Arclight Navy Seal Join Date: Jun 2008 Location: Land of windmills, tulips, wooden shoes and cheese. Lots of cheese. Posts: 8,467 Downloads: 53 Uploads: 10	About matching the RAM & CPU: I've got my memory at 1066, CPU at 1333. I don't think a CPU at 1066 FSB would be better. Yes everything would be running in sync, but I sincerely doubt it would make up for it. Uhm... now that I think about it: true bus speed for Intel CPU at 800MHZ=200MHZ; FSB gets "quad-pumped" to 800 True speed for DDR2 at 800MHZ=400MHZ; it gets "double-pumped" I think that if you go into the BIOS and look up the divider, you'll find it's set to "2", not "1" (which would be synced). (all this is making my head hurt, and I'm not even 100% sure...) In my case FSB is slightly overclocked at 355MHZ (initial 333). This gives 1420MHZ external bus for CPU, and 2.84GHZ clock speed. For RAM it gives 533MHZ bus speed, 1066MHZ clockspeed. RAM ratio=3/2 (meaning RAM bus is at 150% of CPU bus). (ouch) In short; I don't think you're system is running synced as it is. The RAM is running on considerably higher bus speed, so moving to a CPU with higher bus speed will only do you good. Please, if anyone has more insight in this feel free to correct any of this. It's hard to keep track of all this stuff. edit: if you want to check you can download CPU-Z; start the program and look under the "memory" tab and see what the FSB to RAM ratio is. It should read "1:1". __________________ Contritium praecedit superbia.* Last edited by Arclight; 04-01-09 at 01:09 PM.