Ram performance and cas/mhz
- Thread starter Lighters
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Try to stick as close to 1:1 ratio with CPU I would say.
So if your CPU Runs @ 430FSB,
It will be better to run the RAM at 860mhz 4-4-4-12 than at 1070mhz 6-6-6-18.
Always try to get the highest fsb for your current timings, for example:
~870mhz 4-4-4-12
~1100+ mhz 5-5-5-18.
So running 890mhz at 5-5-5-15 will be a waste.
So if your CPU Runs @ 430FSB,
It will be better to run the RAM at 860mhz 4-4-4-12 than at 1070mhz 6-6-6-18.
Always try to get the highest fsb for your current timings, for example:
~870mhz 4-4-4-12
~1100+ mhz 5-5-5-18.
So running 890mhz at 5-5-5-15 will be a waste.
Those timings are the length of time the memory controller expects to sit and wait before it throws an error because it didn't get fed data.
The first figure (Column Access Select or CAS) is usually limiting. The speed of the RAM (the MHz figure) shows how often the memory controller will look at the RAM for a response in clock cycles. Again - it's effectively a worst case scenario.
At 1000MHz the memory controller will look at or send the RAM for data 1 million times per second. If the RAM is CAS 4 then the memory controller will happily wait 4 millionths of a second to submit or receive that data. But if the memory controller can place it on the first, second or third cycle, it will do so. Sometimes it will, sometiomes it won't.
So worst case 800MHz CAS4 is exactly the same as worst case 1000MHz CAS5, except the 1000MHz one is talking to the RAM 20% more often so it has a much better chance of getting the information it wants witghin the 5 clock cycles. Imagine a bloke who chats up 10 women a night vs. one who chats up 8. They both have 5 questions to pull on, but you could get her at 'Hello'.
The guy who talks to more women has a better chance of pulling. Going home alone is a blue screen of death.
Anyway - don't get hung up on RAM speed unless you need the MHz to overclock the CPU, in which case, who cares what the CAS figure is? A faster CPU almost always beats fast RAM.
The first figure (Column Access Select or CAS) is usually limiting. The speed of the RAM (the MHz figure) shows how often the memory controller will look at the RAM for a response in clock cycles. Again - it's effectively a worst case scenario.
At 1000MHz the memory controller will look at or send the RAM for data 1 million times per second. If the RAM is CAS 4 then the memory controller will happily wait 4 millionths of a second to submit or receive that data. But if the memory controller can place it on the first, second or third cycle, it will do so. Sometimes it will, sometiomes it won't.
So worst case 800MHz CAS4 is exactly the same as worst case 1000MHz CAS5, except the 1000MHz one is talking to the RAM 20% more often so it has a much better chance of getting the information it wants witghin the 5 clock cycles. Imagine a bloke who chats up 10 women a night vs. one who chats up 8. They both have 5 questions to pull on, but you could get her at 'Hello'.
The guy who talks to more women has a better chance of pulling. Going home alone is a blue screen of death.Anyway - don't get hung up on RAM speed unless you need the MHz to overclock the CPU, in which case, who cares what the CAS figure is? A faster CPU almost always beats fast RAM.
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Surely one of the best metaphors for ram speed vs timings ever
