Optimum tRAS

In past reviews, memory bandwidth tests established that a tRAS setting of 11 or 12 was generally best for nForce2, a tRAS of 10 was optimal for the nForce3 chipset, a tRAS of 7 was optimal for the nForce4/ATI RD480/ULi M1697 chipsets, and a tRAS of 10 produced the best bandwidth on the ULi 1695.

Since this is our first review of a board with the new ATI RD580 chipset, tRAS timings were first tested with memtest86, a free diagnostic program with its own boot OS that will boot from either a floppy disk or optical disk. Bandwidth of OCZ PC3200 Platinum Rev. 2, based on Samsung TCCD chips, was measured from tRAS 5 to tRAS 15 to determine the best setting.

Memtest86 Bandwidth
Asus A8R32-MVP with Athlon 64 4000+
5 tRAS 1879
6 tRAS 1879
7 tRAS 1999
8 tRAS 2043
9 tRAS 1999
10 tRAS 1958
11 tRAS 1958
12 tRAS 1879
13 tRAS 1870
14 tRAS 1843
15 tRAS 1807

The tRAS setting that produced the highest memory bandwidth with the ATI RD580 chipset was 8. The tRas 8 setting was used for all memory testing on the Asus A8R32-MVP Deluxe.

Memory Stress Testing

The Asus A8R32-MVP easily handles 2-2-2-8-1T timings at stock speed. The default setting for Command Rate in the Asus BIOS is 1T, which makes it much easier to assure that the A8R32-MVP consistently delivers top performance than the 2T default seen in the earlier A8R-MVP. We are pleased that Asus decided to implement the more sensible 1T timings in the update to the A8R-MVP.

Running four double-sided 512MB or 1GB DIMMs is much more demanding than running two DS DIMMs, and Asus did not have any special magic here. Like every board that we have tested, except the DFI RDX200, we needed to drop the Command Rate to 2T with 4 DS DIMMs. This really should not be a surprise, since the DIMM timing is primarily a function of the memory controller on the AMD processor. With 4 DIMMs, the A8R32-MVP remained stable with the same aggressive 2-2-2-8 timings that worked best for two DS DIMMs.

Stable DDR400 Timings - 4 DIMMs
(4/4 DIMMs populated)
Clock Speed: 200MHz
CAS Latency: 2.0
RAS to CAS Delay: 2T
RAS Precharge: 8T*
Precharge Delay: 2T
Command Rate: 2T
*8T was determined by MemTest86 benchmarks to deliver the widest bandwidth with the ATI RD580 chipset. While the board would operate at tRAS of 5T or lower all benchmarks were run at 8T.

Overclocking: Asus A8R32-MVP Test Setup
Comments Locked

65 Comments

View All Comments

  • BPB - Friday, February 17, 2006 - link

    This doesn't make sense: "there will never be another Asus product purchased by our company". Why would a business care about overclocking? A business should care about STABILITY.
  • DigitalFreak - Friday, February 17, 2006 - link

    They should have moved the only PCI-E 1x slot to the left. They way it is now, you lose that slot when using a dual slot cooler in the PCI-E 16x slot closest to the processor. Hopefully that will be changed on the AM2 version of the board.
  • aguilpa1 - Friday, February 17, 2006 - link

    a 7800 and 1900 this way we can better gauge the mean performance of the "board" with identical comparison to other previously tested boards because not everyone is going to run out and get a $600 1900 ATI just for this board.
  • Wesley Fink - Friday, February 17, 2006 - link

    We DID test the A8R32-MVP with both the X1900XT and the 7800GTX. If you closely at the standard gaming performance graphs on p.9 you will see the orange bars are the A8R32-MVP test eith the X1900XT and the green bars are the same A8R32-MVP tests with the 7800GTX. The other board results are with the 7800GTX so if you compare the green bar to all the blue bars you are comparing 7800GTX performance on ATI and nVidia. In addition, all the bars are labeled with the test board and test video card to prevent confusion.

    This is explained in Test Setup on p.6, and in my comment above, "We reported both results so you could compare 7800GTX performance to the previous boards also tested with the 7800GTX. Since the X1900XT is the latest and fastest video card the results were included for Reference only. As someone else pointed out, when testing Dual X16 Video you have to run SLI on nVidia and Crossfire on ATI (or Intel)."
  • aguilpa1 - Friday, February 17, 2006 - link

    never mind, I see someone asked the same question, but were not given a reasonable answer anyways
  • BPB - Friday, February 17, 2006 - link

    This is exciting news. But I plan on getting the X1900 AIW, which won't do Crossfire. So, when are we going to see non-Crossfire (Xpress 200-type) versions of this chipset? In the end I may get this board, but I'm hoping I can save a few bucks by getting one without the added cost of Crossfire.
  • Wesley Fink - Wednesday, March 1, 2006 - link

    RD580 is only available as the dual x16 version. With both x16 lanes off the north bridge you can't really leave out a chip, as you can in the nVidia version right now, and lower the price. The single X16 slot and dual x8 Crossfire will be provided by RD480.
  • n7 - Friday, February 17, 2006 - link

    Looks like a superb motherboard for the price!
  • Zebo - Friday, February 17, 2006 - link

    Look perfect to me. Black, high clocker, built like a tank and relativly inexpensive. I wish they had this two months ago - U seen my DFI chipset mod what a PITA to get silent chipset sitting right under card.:( Not only is ATI chispet seemingly cooler leaving us with passive solutions they clock at least as well if not better.

  • Zebo - Friday, February 17, 2006 - link

    Also the gap between PCIe cards is perfect to run water blocks too and well as nV/ATI silencers w/o touching or being cramped..

Log in

Don't have an account? Sign up now