Memory performance competition 1G and 512 gaps

Memory has a great effect on the quality of our computer hardware configuration, but many people do not know how to evaluate the quality of memory, or the impact of memory size on performance, so this tutorial will give you a detailed introduction today. Let's take a look at this issue.

First, we know that there are usually two factors that affect memory performance: memory bandwidth and memory latency. Memory bandwidth is like a pipe traffic, higher traffic is like more data. The memory delay is like the length of the pipe. The shorter the distance, the better the data will flow to where it is needed. These two points affect the performance of the system at the same time, and they affect the performance of the system in different ways:

Memory bandwidth is determined by the bit width of the memory and the frequency of the memory, just like the width of a road. And the speed of the traffic, only the wider the road, the higher the speed to maximize performance. The well-known dual-channel memory design is like expanding the width of the road, which greatly improves the performance of the system. The memory delay is like the number of red lights on the road. The more red lights, the more the vehicle has to stop and start many times, which delays a lot of time and also has a great impact on performance.

In the K7 era, AMD's Athlon series processors use the EV6 bus, the memory bandwidth requirements are not too high, because the Athlon XP processor's EV6 bus operates at 133/166Mhz, the actual bandwidth is 2.1GB /s or 2.7GB /s, bandwidth requirements are not high, the use of ordinary DDR266 or DDR333 memory is enough, dual-channel DDR400 on such a platform is difficult to play its bandwidth advantage.

Why is this happening? Let's take a look at it:

First, let's take the front-side bus as a 133MHz system. The Athlon XP bus width is 64 bits. In addition, the EV6 bus is used, so the bandwidth required by the processor is: 133MHz× 2× 64bit÷ 8=2.1GB/s.

Then we will calculate the bandwidth of the dual-channel DDR266 memory, because the nForce chipset provides two independent 64-bit memory controllers, so it can be equivalent to 128-bit memory bandwidth: 133MHz & times; 2× 128bit÷ 8=4.2GB/s.

We see that in the traditional architecture, due to the bottleneck effect of the processor, only half of the memory bandwidth can be used, which is why the nForce2 chipset does not differ much in single-channel and dual-channel situations. The reason is gone. However, many users have already used 512MB of DDR400 memory, but they can see that the memory is cheap every day. Many users can't help but want to upgrade their 512MB DDR memory to 1G! But upgrade from 512MB memory. How much benefit will it bring to 1G?

Mainstream 3D game software testing: 1G memory advantage really exists

Test Platform:

Benchmark:
< First, let's take a look at some regular tests! In order to test the difference between 512MB and 1G memory, we chose the more common modern DDR400 memory as the test object, and selected the timing of the two used memories as AUTO. This will not affect the test results due to differences in memory timing.

We first conducted some routine tests. The results obtained in 3D Mark03, 05 and AquaMark 3 were also seen. The difference is not obvious. The result of the LAME MP3 Encoder test is that the number is smaller. The better, the test results are 512MB 4 seconds 59, 1G is 5 seconds 04, the time spent on large-capacity memory has become longer?