What's the best CPU for my DDR2 system?

llawer

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WHAT WILL BE THE BEST PROCESSOR FOR MY LAPTOP supporting only DDR2 800MHZ RAM ?


Hi,

I have a DELL STUDIO 1555 supporting only DDR2 memory RAM (not possible to further upgrade).


IF my current ddr2 memory is 800 MHZ is there any point in getting a 1066 mhz type processor or will it be a waste of money bearing in mind that I cannot upgrade memory to 10666 mhz? (in other words will I gain at all from the extra processor speed?)

Am I right or wrong in assuming that the most useful processor for my system will be the best one I can find in the 800 mhz (FSB) processor category range to match my system's installed RAM of 800 mhz ?

Regards,
DW
 

llawer

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I mean if my DDR2 installed ram is only 800 mhz speed then will installing a processor with more than 800 mhz FSB just be a waste of time as the system memory won't be able to catch up with it, OR NOT ?
 

llawer

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YES I KNOW IT WILL but I have often read that the system memory cannot keep up with the processor speed SO...
 

misry

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SO don't allow the processor to run at 1066, (it shouldn't be able to). Make sure it's throttled to 800. Anything more is "overclocking".

Correction: Don't allow the fsb to run at 1066. And as this is a laptop I believe the question is moot anyway. The most you can get onto this system is a T6600 so any gains you have would be more trouble than it's worth.
 

llawer

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MISRy
and if you can explain to me why the most I can get is T6600 I will be grateful.

simon12
why then do i read that the processors are too advanced for the memory and the memory just cant keep up?
 

misry

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It's the highest rated CPU Dell offers for that model. While you may be able to get a better rated CPU to work in the system you are then talking about degraded battery life, unaccounted for levels of heat, and any number of issues that may crop up.
 



You read wrong. Memory speed and Processor speed are not interrelated on that level, and Processors are almost never held back by memory performance.


Also - Laptops generally don't get "upgraded". They get replaced with a new one. As ably pointed out by MISRy, you have a very limited choice and what choice you have isn't very good to begin with.
 

llawer

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I kind-o disagree in some ways. I think that my choice of processors is better than T6600 (MISRy). If T6660 is my very upper limit can anybody EXPLAIN why? Thanks.
 

llawer

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Thanks for the battery and heat comments but the battery issue is not an issue for me as mostly (80%) I run my laptop without it anyway.

Would anyone disagree with T6600 as THE most suitable processor regardless of what DELL say. I know there are better/faster 800 FSB processors. What about T9500 for example? What might be possible problems running that one?

Thanks.
 
Running a CPU with a higher FSB than the speed of your memory is not detrimental to performance in any way. It just means you could run faster memory and running said memory would improve performance.

As for CPU compatibility, there are 3 issues that need to be covered.

1. Socket Compatibility. First, the CPU must be compatible with your current socket. If it doesn't fit, it won't work.
2. Chipset compatibility. There are many motherboards out there that are compatible socketwise with new CPUs but will not work because the chipset is too old.
3. Bios updates: A CPU must be recognized properly by the bios. Often a new CPU will come out and the bios is unprepared for it so the motherboard vendor will release an update for compatibility. OEM manufacturers (Dell, Acer etc) lock down their bios and do not support new chips in bios updates because they would rather you get a new computer.

What might be possible problems running that one?
Running a CPU not supported by the OEM could work but is unlikely due to the above issues. It could also work, but not be detected properly, resulting in incorrect bios settings for the CPU. There is no way to no for sure except to try.
If, somehow, it does work, there is an additional issue worth mentioning for laptops:
The cooling of the laptop is only designed for the CPUs that could originally come with it. A CPU that runs hotter may not be sufficiently cooled.
 

llawer

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Cheers ENZO for your valuable comments.


I will search them all out.

From your comments and what I see on Intel site the Mobile Intel® GM45 Express Chipset seems to be able handle most processors other than new i3, 5, 7 ones.

I will try pick a much faster than current installed T4200 processor with same FSB (800) and also the same 35 tdb Watt CPU.

So I am pretty certain I'm OK on your point 2 issue from Intel's website chipset/processor compatibility list.

That compatibility should also give me hefty assurance on the socket issue (your first point) being OK.

I just now need to do my homework on your BIOS comment I think.


Thanks again.


ANY DELL 1555 USERS OUT THERE SUCCESSFULLY/HAPPILY UPGRADED FROM T4200 TO A MUCH HIGHER PROCESSOR WITH DDR2 RAM PLEASE LET ME KNOW. NOT MANY COMMENTS OUT THERE FOR ME TO GO ON.