Archived from groups: alt.comp.periphs.mainboard.aopen (
More info?)
Hi Paul,
Thanks for the reply, after reading your advice I'll just stick with what I
have. The pc is about to be replaced as my "main" pc with a water-cooled
one, I'm just
waiting for the Intel 670, XFX GeForce 7800 GTX to come down in price.
I've also read that Creative have a new soundcard due soon.
Many thanks for the advice
Matt U.K.
"Paul" <nospam@needed.com> wrote in message
news:nospam-2507051554140001@192.168.1.178...
> In article <wcidnd_T_Nuyg3_fRVnytQ@pipex.net>, "Matt U.K."
> <mm_lewis@_No_SpAm_hotmail.com> wrote:
>
>> Hi,
>>
>> In an effort to gain more performance I would like to install "faster"
>> (Dual-Channel 2x 512) memory in my gaming pc, according to
>>
http://www.crucial.com/uk/store/listparts.asp?model=AX4R+Plus&tabid=PM
>> web
>> site my choices are:-
>>
>> DDR PC2700
>> Ballistix DDR PC3200, PC4000
>> Ballistix Tracer DDR PC4000
>>
>> As I'm running a 533MHz fsb Pentium (3.06GHz) what speed of memory (2x
>> 512)
>> would you guys recommend for the best performance?
>>
>> Cheers
>>
>> Matt U.K.
>>
>> p.s.
>>
>> The motherboard manual mentions PC-1600, PC-2100 and PC-2700 DDR DRAM
>> speeds
>> but the web site shows speeds up PC4000 as compatible hence my question.
>>
>> Machine Spec:-
>>
>> Motherboard: AOpen 'AX4R Plus' Intel E7205 Chipset (Granite Bay).
>> Processor: Intel 'Pentium 4 3.06GHz' (Northwood,533 FSB) Socket 478.
>> Memory: 1GB 'Crucial' PC2100 DDR.
>
> When a memory is listed at PC4000, that is a measure of how fast the
> clock on the memory can be pushed. But, the motherboard also has to
> be able to run that fast, to get the good out of it. It would be
> like putting performance tires on a VW bus.
>
> I went to the Intel site and looked up the 7205 Granite Bay Northbridge,
> and the 251937 datasheet says:
>
> "Memory System...
> Synchronous operation with processor system bus (same clock
> frequency required on both) "
>
> What this means, is if you have a FSB533 processor:
>
> Processor clock 133MHz x 4 (four transfers per clock) = FSB533
> Memory clock 133MHz x 2 (two transfers per clock on DDR) = DDR266
>
> DDR266 x 8 bytes per transfer = PC2100 (2.1GB/sec)
> Dual channel max transfer rate = 2.1GB/sec x 2 = 4.2GB/sec
>
> Your current PC2100 memory is perfectly matched to your
> processor - that is because its maximum capability (DDR266) is
> being exactly used by the FSB533 processor's choice of clock signals.
>
> A typical overclock for a processor using the 7205 is a little
> over 160MHz. If you repeat the math above, that clock rate would
> be handled by DDR333 (PC2700) memory. Select a memory which is
> CAS2 at PC2700, should be a good match for your board while it
> is being overclocked. You could buy PC2700, PC3200, PC3500, PC4000,
> but they will all operate at a little less than PC2700 in most
> cases, as the processor cannot be pushed any further. (Pushing
> the 133MHz to 160MHz doesn't come with any guarantees, and I'm
> not certain as to which part is the limiting factor, processor's
> bus interface, or Northbridge's bus interface.)
>
> Go here, select "Pentium 4 3.06" in the Intel section.
> 3.5GHz core on air seems to be possible. (3.5/3.06)*133 = 152MHz.
>
http://www.cpudatabase.com/index.cfm?action=search
>
> You could attempt to overclock, even using your current PC2100
> RAM. Now, I don't have your board, and the downloadable manual
> doesn't show BIOS screens, but what I would try is:
>
> 1) Set new processor frequency. Bump Vcore voltage a bit to
> compensate for the higher frequency. Use values in cpudatabase
> as a guide, and use common sense. (Huge Vcore makes processor
> hot!)
> 2) Then visit memory timings - switch from auto to manual.
> The BIOS should have already calculated the new memory timing
> values, based on your new processor frequency choice. When
> a memory is rated for 133MHz, and you want to run it at 160MHz,
> bump Trcd by +1, as that is often enough to get the memory
> to run at the slightly higher clock rate. (I'm assuming here,
> that the BIOS has already calculated the correct value for
> tCAS.)
> 3) Save and exit. If the computer will POST, boot with a memtest86+
> test floppy, from memtest.org . You should not attempt to
> boot into Windows, until memtest is clean for a couple of
> complete passes when using the new settings.
>
> Start with small changes first, like 133-138-143-148-152.
> You might be able to see stability fall off, without having
> to clear CMOS and reenter all BIOS settings. (Unplug computer
> before clearing the CMOS. This protects the CMOS battery
> path.)
>
> The other things you might want to optimize, is the CAS value.
> tCAS is in fact a time number, like 15 nanoseconds. It is the
> time until the data comes out of the memory chip. It is
> quantized into clock cycles. I.e. 3 clock cycles of 5ns each
> exactly equals 15ns. 2 clock cycles of 7.5ns each is also
> 15ns. A 5ns clock is 200MHz, equivalent to DDR400. A 7.5ns
> clock is 133MHz, equivalent to DDR266. What that means is,
> if you bought a PC3200 CAS3 memory, when run at DDR266, it
> becomes a CAS2 memory. Running CAS2 on your board will be
> the lowest latency you can get for your memory. You could
> either buy a PC3200 CAS3 memory or a PC2100 CAS2 memory,
> and they would both offer CAS2 operation at the DDR266
> (PC2100) rate. (If your current memory is CAS3, then you
> cannot select a value lower than that. A lower CAS number
> might be an option if you do decide to buy more memory.)
>
> The PC4000 memory you mentioned above, would be good under
> two conditions. You buy an (obsolete) DDR based motherboard
> that supports a FSB800 processor, then you overclock the
> FSB by 25% and wish to run the memory in sync with the
> processor bus. PC4000 memory is "overclocker" memory - it
> is only good value for the money, if you plan to run
> overclocked to FSB1000 all the time (machine will run
> hot and warm the room up). And don't plan on using four
> sticks of PC4000 - it is really a 2x512MB deal only.
> 4x512MB double sided memory cannot be run at DDR500, due
> to the limitations of signal quality on the memory bus.
>
> What you do next, is a function of whether you think the
> "bleeding edge" is really going to buy you something. Your
> system, like mine, is a previous generation, and reuse
> opportunities are limited. Spending $100 on a FSB800
> motherboard, gives you a little room for an upgrade, but
> the clock rate of the processor really isn't going to go
> much higher (at least at a price you can afford). So,
> even if you bought a 3.2GHz FSB800 processor, on core clock
> limited applications it is only going to go a tiny bit
> faster. If you had deep pockets, you could buy a slightly
> faster processor than that, but not by much.
>
> For gaming, AMD is another option. With memory dividers,
> you could initially reuse your memory. A S939 dual channel
> board, would match the dual channel nature of your current
> board. DDR memory is still cheap, so buying 2x512MB PC3200
> memory would help a bit. But, once the clock rate on the
> AMD processors gets "interesting", the price is again
> a little too high. (Overclocking is still a viable option.)
> But, with careful shopping, at least if you bought a S939
> Athlon64 based board, you can use a single core processor
> or a dual core processor, reuse your AGP video card, and
> use whatever DDR memory you manage to scrape together.
>
> Conclusion: Be happy with your current config, or be prepared
> to fork out more dough. Buying a slightly faster memory
> for your board, while it would make room for an overclock,
> is not an entirely risk-free choice. (Depending on the BIOS,
> overclocking might not even be possible. Some 7205 boards
> have better BIOS than others.) Experiment with your existing
> hardware, and see if you like overclocking - it is a bit like
> learning to drive a manual transmission, expect to stall it
> a few times, before you get the hang of it
>
> Paul
Facebook
Twitter
Instagram