Does RAM FSB affect Processor speed

Howdy guys. I have a question I'm not sure about.
I'm building a new computer and using an Asus P4P800-PE with a 2.68C type processor (800 fsb, hyperthreading, Prescot) but am considering using some older Mushkin basic 2700 RAM. I'm wondering if the older RAM will impede the processor much. I believe the RAM is 266 DDR.
Is this an ok combination, or should I opt for the faster 3200/3500 RAM. I guess I'm asking if the performance difference is worth buying the newer RAM or sticking with the older RAM I already have, and upgrading when I get some more money.
Any thoughts appreciated.
Thanks.

 

im almost positive its the processor that affects the ram speed and not the otherway around

 

It depends. 800FSB (well, 400 really..) means that in order to take advantage of the processors high FSB, you need ram that goes at least 400Mhz. Bear in mind that the motherboard needs to support that too.. strangley enough, googling that motherboard gives me nothing :/. So for that setup youd need PC3200 DDR to take advantage. Either that or get a processor with a slower FSB (333/666, like my Athlon XP 3000+).

If you try and run the system at 400/800 FSB, then your ram will crap out. You would need to run at 333 (or multiple) which wouldn't be taking advantage of the CPU.

 

Hi,


i agree with Goldfish, you would have to underclock that cpu to run at the ram clock 166.

Get better memory or a slower cpu.

rick

 

Theoretically, running RAM and CPU at the same speed improves synchronization of data transfers, and offers optimum use of the data. There's less waiting time between the cpu issuing a command, and the ram being ready to receive/act on that command. Running ram faster than the cpu is a mixed bag. The nForce dual channel boards actually run more efficiently with cpu & ram at the same speed than using faster ram. Less time spent waiting for the clock cycles to match up. Non-nForce boards usually show faster processing time with faster ram. Evidently the faster transfer time overcomes the waiting liability.

Running ram slower than the cpu takes a double hit. You not only have the waiting time associated with clock cycles that are out of sync, you also have straightforward slower data handling speed.

Most motherboards today allow asynchronous clock speeds, where CPU and RAM clock can be set independently, so yes, you can run the slower ram if you want to. Check the motherboard's specs for what speeds it will take, but most likely you can run the slower ram at it's rated speed, and add faster stuff later, without underclocking your CPU.

 

Appreciate the very informative answer GT.

K

 

Thanks G.T. and everyone else for an answer to this. The motherboard specs state that it can take PC2700 RAM ok, and at this time it looks like that is how it's going to be built. When funds lossen up some (thks tax man) then we will up it to PC3200. I just didn't want a big bottle neck in there showing up from the 2700 RAM.
Again, thanks. This is the place I check first for the answers I need. Lots of knowledge hanging around in here

 

Ah yes, i forgot about this! That is certainly a good point