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


View All Comments

  • Spinne - Monday, March 6, 2006 - link

    NewEgg still doesn't have them in stock, neither does Monarc Computers. Wonder how long it'll be before they get them and the prices drop. Reply
  • dennis hs - Sunday, March 5, 2006 - link

    I've just gotten this mobo.. It's pretty sweet! I really like the ALC882 onboard sound! It's really crispy and all good :D

    Overall I don't have any issues with it. It's a damn good mobo!

    [vietnamese hooker mode on]
    " Me love it longtime :) "
    [vietnamese hooker mode off]
  • tonser - Friday, March 3, 2006 - link

    It is nice that manufactors listen, but why do they still bring out Motherboards for SLI and Crossfire, where the normal PCI cannot be used with their heigh end grafic cards - I am wondering ? Reply
  • yacoub - Thursday, March 2, 2006 - link

    This board gets an official "daaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaamn, Gina!" rating.
    Holy crap it flies with an X1900XT!
  • theOracle - Wednesday, March 1, 2006 - link

    In the table - "PEG Bugger Length" Reply
  • Wesley Fink - Monday, March 6, 2006 - link

    Corrected the Brokeback Mountain reference Reply
  • DigitalFreak - Wednesday, March 1, 2006 - link

    No one has any RD580 boards in stock in the US. Hell, Newegg doesn't even have any listed! Looks like another classic paper launch to me. Reply
  • glynor - Wednesday, March 1, 2006 - link

    http://www.newegg.com/Product/Product.asp?Item=N82...">Oh, and how about from Newegg here Reply
  • SLIM - Wednesday, March 1, 2006 - link


    Please get a clue before posting. All these people complaining about not making proper comparisons because Anandtech went the extra step of testing the latest vid card from ati on their latest chipset in ADDITION to making a very fair comparison with what nvidia has to offer currently.

    Nice article, too bad people don't pay attention to the graphs before they complain about them.
  • DigitalFreak - Thursday, March 2, 2006 - link

    Moron. Did you happen to notice the "Out Of Stock" button?

    And what's with the bitching about proper comparisons, blah blah blah? Reply to the wrong thread, did we?

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