FSB 533 v 667

Hi,

I have an ASUS F3F, 1.73 Core Duo, 2 GB 667 RAM, FSB 533, 80 GB HD (only 40% currently used).

Does the fact that my FSB speed is less than the RAM mean that I am only getting a maximum 533 speed out of my 667 RAM?

Would it be worthwhile upgrading the processor to a Core 2 Duo 2 GB or better? I am using mainly office applications but I can have multiple programs running at once and am finding the computer is not responding as fast as I would like.

Thanks

 

Yes, that is true, it'll downclock it to 533mhz. You can upgrade your CPU to a Core 2 Duo at 667mhz, but it'll void your warranty.

 

I'm a little confused. I also have a Core Duo CPU in my laptop. It's a T2500 2GHz and the FSB is 667MHz. What makes my FSB 667 and nshore's only 533? BTW, we both have the same memory. I was pondering upgrading my CPU to a Core2Duo 7600 but the $650.00 price tag didn't make the so-so performance boost on my rig worthwhile. Just curious about the nshore's RAM report thank you.

 

Hi,

The reason why your computer has an FSB 667 and mine has an FSB 533 is simply because that is the way the computer was configured by the manufacturer. Your higher FSB enables you to run 667 RAM and get more use out of it than I do. Regarding your proposed purchase of C2D 7600, you would notice a difference in speed if you upgrade, partly because the cache size is larger and partly because the processor is almost 20% faster but the difference would not be enough to warrant the change if all you are doing is office apps. The change would be more relevant if you were doing VDO streaming for example.

 

Thanks for the reply. I thought the FSB speed was in the hardware design. Another reason I hesitate on a CPU upgrade is because my Yonah CPU (667FSB) will not fully utilize the new 800MHz FSB like the Santa Rosa chipset. Oh well, I may still jump if the price comes down. Right now I'm very pleased with the performance of my W2jB. It runs newer graphics intense games pretty darn smooth.

 

currently, the santa rosa notebook platforms run ram at 667

 

Sorry but there is a misinformation in this thread.

Your FSB rating is done by instructions given per section. An 800 MT/s FSB which is equivalent to having an 800 MHz frequency FSB, communicates through the north and south bridges of the chipset at that speed.

The FSB speed is actually apart of the hardware design, but it is limited by the FSB rating given by your processor, since every single process or code execution has to happen through the processor. So if your processor has an FSB rating of 667 then that is what the entire board will run at. But if it is rated at 800 Mhz then that is the speed of the communication to the processor and back.

The speed at which your RAM will relay information from the Harddrive to the RAM and through the processor will only function at its maximum speed and the maximum FSB speed. So if you have 667 Mhz RAM then yes your RAM will relay the information through the processor at that speed

But actually the communication between your Hard Drive and processor will function at 800Mt/s if that is the rating on your processor. Similarly the Graphics processor relaying information from the hard drive and the RAM and through your CPU which handles much of the physics in games, will function at 800MT/s.

So your RAM speed is only a small determinant in the actual speed of your system. The FSB is essentially the means of communication with every component attached to your computer, including PCI cards and the likes, to the processor.

 

But still, I've been seeing information that 800 Mhz ram will downclock to 667 on the santa rosas right now. Is that true?

 

yes the current santa rosa chipsets only allow up to 667mhz ram, despite the cpu being 800mhz fsb

 

Yes that is absolutley correct. Santa Rosa does not actually support 800 MHz RAM, or PC2-6400, but will throttle down to 667 Mhz. AMD's new Tyler core using the 65 nm fab proc, does support PC2-6400 RAM. This includes the the Turion X2 TL-56, 58, 60, 62, 64.