Both T7100 and T5550 is based on Santa Rosa platform (65nm)
As you've said T7100 has 800MHz FSB while T5550 has 667MHz.
However, for all Santa Rosa platform chips, only DDR2-667MHz is supported. 800MHz RAM on a T7100 will be only running 667MHz!
Also if you noticed, Clock speed for T7100 is 1.80GHz vs 1.83GHz for T5550. The difference should be very little.
This due to the frequency stepping.
T7100's 9x 200Mhz vs T5550's 11x 166Mhz
(M0 stepping vs L2 stepping)
Intel Dynamic Front Side Bus Frequency Switching is only supported for M0 stepping I think. This feature will save you power@battery when your CPU is idle. It will throttle down the FSB frequency when idle.
One more difference is Intel's VT (Virtualization Technology) exists in T7100 but not T5550. Basically this feature will be useful if you use Virtual machines. If not it shouldn't be too much of a concern.
My conclusion is that
1) T7100 is better for power saving and if you run VM wares, it will be faster than VM on T5550.
2) If you don't care about CPU idling power savings and VM ware processing overheads, there's negligible difference for computing performance.
" In newer systems, it is possible to see memory ratios of "4:5" and the like. The memory will run 5/4 times as fast as the FSB in this situation, meaning a 133 MHz bus can run with the memory at 166 MHz. This is often referred to as an 'asynchronous' system. It is important to realize that due to differences in CPU and system architecture, overall system performance can vary in unexpected ways with different FSB-to-memory ratios. "
Ok, I'm really confused at this point, and would like some clarification. I used to work for a chip company, so some of the tech lingo is famliar. I'm going to make a slew of assumptions and would appreciate it if you can correct me where I am wrong (I KNOW I'll be wrong in a few places), just so I can get a better understanding of what I have. Thank you in advance for your patience and consideration: I'm assuming that when you say this is a 65 nm architecture that you are referring to the physical process used in the Fab during chip production. I'm aslo assuming that the FSB is pushed by the CPU chip, not drawn by the surrounding chips (where is the signal generated?). I'm also assuming that the "support" for this chip is either the surrounding chips, or the software / firmware that runs this chip and / or the chips around it. I'm also assuming that the manufacturer (Intel in this case) is claiming that this chip is an 800 MHz FSB chip. I guess my biggest confusion is in why they would make that claim if it were physically impossible for anyone to ever reach that speed (even them) if the support for those speeds doesn't exsist? I mean, is this a limitation that is built into the chip itself, or is the missing support for 800 MHz ever going to be made available? What should I be looking for, and is there any idea when (or if) its going to be made available?
thanks in advance again.
Just some quick clarification... FSB is the signal frequency that your motherboard sends to the CPU. The chip manufacturers take a set FSB, and amp up the multiplier on a CPU until it becomes unstable, then back it off a bit. (CPU speed = effective FSB * multiplier number) I say effective fsb, because different CPUs do different things... Some take the motherboard FSB and multiply it by 2, 4, or have a different setup entirely. But that's how manufacturers find out what to run a certain CPU at. Now, you could always amp up (or down) the FSB, and you would change your overall CPU speed. The trick is, if you mess with FSB speeds, you mess with all the components of the computer, not just your CPU / RAM, but even your controllers / northbridge. That's why it is nicer to get an unlocked CPU for overclocking, because you can just change the multiplier. As for 800 FSB, yes, it exists. I'm not sure your confusion.
I guess I wasn't too clear in the reason of the question. Sorry. BP112 had stated that only 667MHz Ram was supported by this chip, and that 800MHz RAM would only run at 667MHz. So, if the chips on the Motherboard are sending an 800MHz FSB signal to the processor, why is it that the same signal isn't supported at the RAM? Its been quite a while since I've worked with O'Scopes and individual components, but as I remember, if you had to cater to the weakest component in the system when setting signal strength. Thanks again.
Actually bp112, the t5550 does have Mo core stepping, intels own web sight says so and my experience shows it to be true. I left my laptop on, unplugged, over 24 hours, closed lid, and when I opened it it went right back to the web page I was on and 3/4 battery life left!