tRAS and Memory Stress Testing

Memory tRAS Recommendations

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, and a tRAS of 7 was optimal for the nForce4 chipset. The recently tested ULi 1695 was best at tRAS of 10.

Since this is our first review of a new ATI 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 12 to determine the best setting.
Memtest86 Bandwidth
Sapphire PURE Innovation with Athlon 64 4000+
5 tRAS 2048
6 tRAS 2092
7 tRAS 2141
8 tRAS 2141
9 tRAS 2092
10 tRAS 2048
11 tRAS 2004
12 tRAS 1922

Two things stood out in our tRAS tests. First, the Sapphire ATI exhibits the best bandwidth at a tRAS setting of 7 or 8. We decided to use 7, since it is the same as the best setting for nForce4. Second, the bandwidth numbers on the ATI were a bit higher across the tRAS tests than what we saw with the ULi 1695. This suggests ATI having better optimized memory management - at least at this stage of development.

Memory Stress Test

Our memory stress test measures the ability of the Sapphire ATI to operate at its officially supported memory frequency (400MHz DDR), at the lowest memory timings that OCZ PC3200 Platinum Rev. 2 modules will support. All DIMMs used for stress testing were 512MB double-sided (or double-bank) memory. To make sure that memory performed properly in Dual-Channel mode, memory was only tested using either one dual-channel (2 DIMMs) or 2 dual-channels (4 DIMMs).

Stable DDR400 Timings - One Dual-Channel
(2/4 DIMMs populated)
Clock Speed: 200MHz
CAS Latency: 2.0
RAS to CAS Delay: 2T
RAS Precharge: 7T
Precharge Delay: 2T
Command Rate: 1T

Using two DIMMs in Dual-Channel 128-bit mode, the memory performed in all benchmarks at the fastest 2-2-2-7 timings at default voltage, which was the only memory voltage available.

Stable DDR400 Timings - 4 DIMMs
(4/4 DIMMs populated)
Clock Speed: 200MHz
CAS Latency: 2.0
RAS to CAS Delay: 2T
RAS Precharge: 7T
Precharge Delay: 2T
Command Rate: 2T

Tests with all four DIMM slots populated on the Sapphire required a 2T Command Rate with 4 DIMMs in two dual channels. This is the pattern seen on other top-performing Socket 939 boards. The Sapphire AMD had no problem running at a 200 CPU speed setting with 4 double-sided DIMMs. Since the Athlon 64 memory controller is on the processor, there were no real surprises in the memory stress tests. The Sapphire ATI is certainly competitive with the best Socket 939 boards in memory performance.

Overclocking: Sapphire PURE Innovation Test Setup
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  • Avalon - Friday, July 29, 2005 - link

    This board sounds fantastic!
  • Hacp - Friday, July 29, 2005 - link

    Competative with similar Nforce4 boards(DFI LP) isn't enough. They need to beat the price by 5-10 dollars in order to regain the edge. I agree that the VTT options is awesome (for you BH-5 users), but in order to kill the current proven top Overclockers board, they need to be very competative with the DFI in terms of price.

    Also, I was wondering if they managed to fix the cold boot issue with these boards. If the cold boot issue is a non issue with these boards, and they are priced exactly the same as the DFI Lan Party boards, then it is a no brainer for BH-5/CH-5/UTT users as to which board to pick (unless they already are doing the 3.3 Rail Vdimm mod).

    Also, the 2nd page, He art in the first sentence needs to be fixed, and in the first page, it says AMD in the first paragraph when its supposed to say ATI.
  • afrost - Friday, July 29, 2005 - link

    I don't think so, a lot of people complain about problems with the DFI.....and it has a super loud fan on the chipset which is difficult to replace because the video card is right on top of it.

    I personally would never buy a DFI....different people obviously have different priorities

    If this board is rock solid stable like AT reported, then they will have a winner.
  • cryptonomicon - Friday, July 29, 2005 - link

    looks like a strong competitor, and here was a typo pg. 11
    "The Sapphire ATI chipset performs at least as fast as the best of nForcee4 chipset boards"
  • Mant - Friday, July 29, 2005 - link

    I think that was intentional. They're comparing the ATI to the "NForcee" by MVidia...like you can compare a Seiko watch to a BOLEX
  • RyanVM - Friday, July 29, 2005 - link

    In the first pic of the motherboard, it clearly has 8 SATA ports. However, the next page lists the specs with 6 SATA ports and the next picture seems to confirm that. Is there indeed an 8 SATA port version as well?
  • Wesley Fink - Friday, July 29, 2005 - link

    The pictures on page 4 were provided by Sapphire and are earlier prototypes. The actual production version we tested is pictured on page 5 and has 6 (not 8) SATA ports. We apologize for the confusion. There are indeed pads for 8 SATA ports on the production board, so there could be further developments.
  • ncage - Friday, July 29, 2005 - link

    What i like:
    Performance in general
    good audio quality (im wondering if it supports any of the eax extensions though which would be great if it did. Would elimante the need for a sound card.)

    What i don't like:
    bad USB2 performance. This would affect me big time. I have a pro consumer camera (8MP Olympus C-8080) and i usually transfer a bunch of images at a time from my camera to my computer so this is definitly a disapointment.

    I really like nvidia as a company. Their driver team has from the start been top notch. I think that is one of the things that led to their popularity. I generally have always gone with nvidia except in the 9800 pro days because you know why. I currently own a 6600gt which i love. Anyways the only thing that upset me that nvidia did was to take out soundstorm out of thier chipsets. I hope ATI bringing high end audio will force nvidia to reconsider. Nvidia knew that a lot of customers were asking for soundstorm back yet they still wouldn't put it back in. I just don't understand this.

    I hope thier are boards produced that don't have dual video card abilites because of price. I really don't want two video cards. I only occasional play games and im not going to spend 500-900 on two video cards. So we shall see how this plays out.
  • bob661 - Friday, July 29, 2005 - link

    The mobo manufacturers were griping about the price. Also, I believe the demand was too low. Yes I know lots of geeks liked it but we're a small percentage of the market.
  • BPB - Friday, July 29, 2005 - link

    "Today, we look more deeply at production version of the ATI Grouper that will be launched by Sapphire next week."
    So, when do we actually see these? If it's by end of Summer, great. If not, it may just be too late. I think most people who've waited for ATI to get this out have already gone to nVidia. I know my buddy has.

    Also, regarding Crossfire, can an AIW X800XT PCIe work with a plain old X800XT PICe?

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