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toostrike22 · January 22nd, 2006, 09:19 AM

I have been taking a crash course on learning about ram……….

Basically, you need memory that provides at least as much bandwidth as your processor and has the lowest CAS you can find or afford.You don’t what to dip down below cas latency rating under 2.5

(ie)Cas latency (2) Timing 2-2-2-5

With all things equal, a stick of DDR memory capable of running 2-2-2-5 memory timings will make the computer operating experience seem faster than a DIMM which can only operate at 3-4-4-8. This is because the delay from when the memory receives an instruction, retrieves the data, and sends it back out is less time.*disclaimer-If you have a Cas latency under 2.5,and memory speeds 2-2-2-5,you may sacrifice stability for speed increase.

Most DIMMs that operate at tight timings, such as PC3200 and PC3500 modules, have to run the memory at lower MHz than the system bus to maintain the tight timings. However, when overclocking the microprocessor to extreme speeds these DIMMs are bandwidth limiting the processor unless you loosen the timings so that the memory can run in sync with the front side bus or CPU external frequency.

The signifigance of this is that when the processor requires a great deal of bandwidth, the CPU will have to wait for another clock cycle before being filled, as the memory is just not fast enough to keep up at the same pace. Having a large pool of bandwidth is great when you're working with applications that process a lot of raw data such as Photoshop or databases.

The other point is that CAS2-rated PC3200 and PC3500 memory can make up for the lack of bandwidth because the memory has a lower latency that in effect moves data between the CPU and the memory much faster. Programs that do not require a large amount of bandwidth tend to benefit more from quicker data transfers between the memory and the rest of the computer such as games and 3D applications.

From what I read on Corsair Value Ram it has a Cas latency of (3),which is fine,but they don’t list the timing speeds(bad)The reason they don’t list timing speed is because there looser vs tighter,and I don’t like that,as far as gaming goes.

Corsair Value 2x1g $165 Cas latency 3 Timing Not rated
Corsair XMS 2x1g $194 Cas latency 3 Timing 3-3-3-8

I’ll pay 30 dollars more for tighter timing speeds,and not have to worry about overclocking.

What is your opinion?

January 22nd, 2006, 09:19 AM	#1 (permalink)
toostrike22 Junior Member Join Date: Jan 2006 Posts: 22	Corsair Value Ram vs Corsair XMS I have been taking a crash course on learning about ram………. Basically, you need memory that provides at least as much bandwidth as your processor and has the lowest CAS you can find or afford.You don’t what to dip down below cas latency rating under 2.5 (ie)Cas latency (2) Timing 2-2-2-5 With all things equal, a stick of DDR memory capable of running 2-2-2-5 memory timings will make the computer operating experience seem faster than a DIMM which can only operate at 3-4-4-8. This is because the delay from when the memory receives an instruction, retrieves the data, and sends it back out is less time.*disclaimer-If you have a Cas latency under 2.5,and memory speeds 2-2-2-5,you may sacrifice stability for speed increase. Most DIMMs that operate at tight timings, such as PC3200 and PC3500 modules, have to run the memory at lower MHz than the system bus to maintain the tight timings. However, when overclocking the microprocessor to extreme speeds these DIMMs are bandwidth limiting the processor unless you loosen the timings so that the memory can run in sync with the front side bus or CPU external frequency. The signifigance of this is that when the processor requires a great deal of bandwidth, the CPU will have to wait for another clock cycle before being filled, as the memory is just not fast enough to keep up at the same pace. Having a large pool of bandwidth is great when you're working with applications that process a lot of raw data such as Photoshop or databases. The other point is that CAS2-rated PC3200 and PC3500 memory can make up for the lack of bandwidth because the memory has a lower latency that in effect moves data between the CPU and the memory much faster. Programs that do not require a large amount of bandwidth tend to benefit more from quicker data transfers between the memory and the rest of the computer such as games and 3D applications. From what I read on Corsair Value Ram it has a Cas latency of (3),which is fine,but they don’t list the timing speeds(bad)The reason they don’t list timing speed is because there looser vs tighter,and I don’t like that,as far as gaming goes. Corsair Value 2x1g $165 Cas latency 3 Timing Not rated Corsair XMS 2x1g $194 Cas latency 3 Timing 3-3-3-8 I’ll pay 30 dollars more for tighter timing speeds,and not have to worry about overclocking. What is your opinion?