Can a 1066 fsb mobile cpu work with a mobile mobo with 800 fsb if slot fits or it should depend on bios spec?

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Mandtugai!

I know we're knowledgeable people, but this is supposed to be a help forum for SETI related problems! :)


To answer your question, the answer is that it really depends. Some laptop manufacturers are very particular about the RAM that they will support (determined by the programming of the EEPROM chip on the RAM module known as the Serial Presence Detect or SPD module). If the SPD is not determined to be compatible, then the module will not work.

The problem is compounded by the fact that it varies from manufacturer to manufacturer, and sometimes model by model. Unfortunately, there is no universal database where I could look up your RAM that you have and your laptop model and tell you if it will work, but I can tell you that if you use a RAM manufacturer's configurator, such as what can be found on www.Kingston.com, they will guarantee you that the model listed will definitely work with your laptop.

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Any cpu related knowledge questions still logically relate to crunching matters in this forum if question starter has considerable RAC. I am crunching with my laptop with T8100 cpu but considering to upgrade to more higher crunch power in mobility condition. And many mobile cpu's have same P slot while fsb is different such as 800mhz and 1066mhz. So basically this is my question background.

But if you feel this question offensive or taking advantage of kind probably you can delete this thread. I know seti forum belongs to certain overly western mentality naive culture while the project belongs to everybody. :)

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Mandtugai!

Any cpu related knowledge questions still logically relate to crunching matters in this forum if question starter has considerable RAC.

So nice of you to tell me what belongs where. Actually, this is for Q&A's regarding the SETI software. Any CPU related questions pertaining to crunching should be in the Number Crunching forum. In fact, instead of deleting the thread, I'll simply move it for you. :)

And many mobile cpu's have same P slot while fsb is different such as 800mhz and 1066mhz. So basically this is my question background.

...and the answer remains the same. You need to check with your manufacturer before knowing it will work. Generally, you can use a higher speed RAM module such as 1066 with a slower FSB CPU such as an 800MHz FSB, but some manufacturers do not allow this, so you need to check to make sure.

I know seti forum belongs to certain overly western mentality naive culture while the project belongs to everybody. :)

Your statement has no bearing on the subject matter. Regardless if the SETI forums belong to Berkeley, and regardless if the project "belongs" to everybody, this has nothing to do with starting a hardware-based topic in Q&A when they belong in Number Crunching, nor does it have anything to do with your views on westerners or their naivety, which frankly is a political view that also doesn't belong in this subject thread.

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You keep talking about RAM and he is asking about a CPU, btw.

My laptop will not support stepping up in FSB, but it is BIOS limited. The best thing would be to find out if your model laptop is offered with the higher processor, that would be a good indicator. You could also go to Intel's site and do some research on the chipset of your laptop and see what it supports.

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Daniel

You keep talking about RAM and he is asking about a CPU, btw.

I need to pull myself together.



Let me give a more adequate answer: As long as the system BIOS recognizes the CPU ID and stepping, you can technically use it in a lower FSB bus. But you will lose speed. Why? Because CPUs derive their speed from a FSB multiplier. So a CPU with a speed of 2.4GHz running on a 1066MHz FSB will have a 9x multiplier (because the true speed of the FSB is 266.66MHz, so 9*267=2,400 or 2.4GHz).

The CPU multiplier is locked in most CPUs (and in all mobile CPUs that I'm aware of), so if you were to plug in that same 9x multiplier CPU into a board that uses and 800MHz FSB (or 200MHz true speed), it would only operate at 1.8GHz (9*200=1,800 or 1.8GHz). The only way to gain that speed back is by overclocking the FSB up to 266MHz (1066MHz theoretical), but many laptops do not allow you to change the FSB.

Of course, if the laptop supports the 1066MHz FSB but is only using an 800MHz FSB CPU, then upgrading to the 1066MHz FSB CPU should work (again, assuming the BIOS supports the CPU you intend to use). Just be careful that the extra heat generated by using a faster CPU will be able to be dispelled by the laptop's existing ventilation system - or buy a laptop cooler and never operate it without it.

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The only thing that matters is the motherboard's chipset.
If your chipset support your CPU, then the CPU will work in your motherboard. Everything else is secondary (BIOS) and tertiary (RAM speed).

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