X-bit labs

Meeting First Socket 939 Processors: AMD Athlon 64 3800+ and Athlon 64 3500+ (page 6)

Category: CPU

by Ilya Gavrichenkov

[ 06/01/2004 | 07:59 AM ]

Testbed and Methods

Today, we will test two processors for the Socket 939 platform: AMD Athlon 64 3800+ and AMD Athlon 3500+. Two other newcomers, the Athlon 64 FX-53 for Socket 939 and the Athlon 64 3700+ for Socket 754 will be discussed in our upcoming reviews. Basing on the price tags on the two processors, we took the following CPU models from the opposite camp to compare them with: a Pentium 4 3.4GHz on the Northwood core and a Pentium 4 3.4E on the Prescott core. Besides that, from the Intel camp again, we took a Pentium 4 Extreme Edition 3.4GHz. A couple of older processors from AMD were also thrown into the heap: an Athlon 64 3400+ for Socket 754 and an Athlon 64 FX-53 for Socket 940.

A short remark about the prices: the Athlon 64 3500+ only fits into the same price niche as the Pentium 4 3.4GHz and 3.4E, while the price tag of the Athlon 64 3800+ ($720) is similar to that of the Athlon 64 FX-53 and has no alternatives on the Intel part, because Intel sells its Extreme Edition of the Pentium 4 at a price much higher than $900.

We used the following hardware in our tests:

• Processors:
• AMD Athlon 64 FX-53 (Socket 940);
• AMD Athlon 64 3800+ (Socket 939);
• AMD Athlon 64 3500+ (Socket 939);
• AMD Athlon 64 3400+ (Socket 754);
• Intel Pentium 4 3.4E GHz (Prescott core);
• Intel Pentium 4 3.4GHz (Northwood core);
• Pentium 4 Extreme Edition 3.4GHz.
• Mainboards:
• ASUS A8V Deluxe (Socket 939, VIA K8T800 Pro);
• ASUS P4C800-E Deluxe (Socket 478, i875P);
• ASUS SK8V (Socket 940, VIA K8T800);
• ABIT KV8-MAX3 (Socket 754, VIA K8T800).
• Memory:
• 2x512MB DDR400 SDRAM (Corsair CMX512-3200LLPRO, 2-3-2-6 timings);
• 2x512MB Registered DDR400 SDRAM (Mushkin High Performance ECC Registered, 2-3-2-6 timings).
• ASUS RADEON 9800 XT graphics card with the Catalyst 4.5 driver;
• Western Digital Raptor WD740GD had disk drive.

We ran our tests in Windows XP SP1 with DirectX 9.0b installed.

Synthetic Tests of the Memory Subsystem

We haven’t yet met a dual-channel memory controller from AMD with support of faster non-registered modules of DDR SDRAM, so we first examine its performance in synthetic tests. We use the ScienceMark 2.0 utility which offers a good toolset for exploring the memory subsystem. First of all we measured the bandwidth and the latency of the memory subsystem in platforms with different Athlon 64 processors (Socket 939 Athlon 64, Socket 940 Athlon 64 FX and Socket 754 Athlon 64). To be able to compare the results correctly, we made all the processors work at 2.2GHz. Moreover, we added the results of Pentium 4-based systems, in which the processor was clocked at 3.4GHz.

As the table suggests, the memory controller integrated into Athlon 64 processors shows a miraculous performance. As you know, the AMD64 architecture puts the memory controller into the CPU die and clocks them both at the same frequency. This trick brings such benefits as higher memory bandwidth and lower latencies compared to Pentium 4-based systems.

The memory controller of the Athlon 64 3500+ works with dual-channel non-registered memory and it is really faster than controllers of both Athlon 64 FX-51 and Athlon 64 3400+. In comparison with the first of these two CPUs, the Athlon 64 3500+ wins due to the use of non-registered memory. In the second comparison, it wins due to the dual-channel architecture with the bank interleave feature. Well, I should remind you that the memory controller of the new Athlon 64 for Socket 939 can only show such high results if you use the 1T timing.

To confirm the highest performance of the memory controller of the new AMD processors, I’d like to show you the numbers I got in the memory test of SiSoftware Sandra 2004:

Really, Sandra 2004 says the practical bandwidth of the memory subsystem of the Athlon 64 3500+ is 92% of the theoretical maximum and that’s very good. For example, the i875P-based system enjoys only 78% of the theoretical bandwidth. In fact, only Athlon 64 CPUs with a single-channel memory controller can boast a higher efficiency, reaching to 96% of the theoretical memory bandwidth.