Originally posted by: Zero1
to clear that up:
DDR stands for Double Data Rate dimm= x2
SD single sided dimm= x1
u can use DDR as single channle if you want poor profoarmance, but i know of NO way to-run as DDR not SD on a single ram chip. look this up if you want, but to run in true DDR mode you need a pair of ram sticks. if you have any idea of how Rambus ram works(SAME as DDR) then you might know why it is NOT posiable to run on both peak and low clock pionts with one ram stick.
that said: I have no idea how to flash bios without post, but when i purchased my setup both places of purchace(1cpu 2mobo) warened me i may have to flash bios prior to getting my cpu/mobo to post
You're wrong again...
DDR is double data rate, which mean that for each clock cycle, data is transfered at the rising part and the falling part on the clock cycle. which mean that when the signal rise from 0 to 1, that one bit is transfered and when the signal fall from 1 to 0 another bits of data is transfered. 2 bit for 1 clock cycle...DDR. SDR need an entire clock cycle to transfer 1 bit. RAMBUS is serial RAM which works as QDR, quad data rate. 1 bit of data is transfered when the clock start to rise, 1 bit when it stop to rise, 1 bit when it start to fall and 1 bit when it stop to fall ...and the cycle goes on. 4 bits for each clock cycle. That was the bandwidth needed for the P4 to perform, as it is bandwidth ungry... in order to acheive the same performance with DDR, dual channel was created. 2 x DDR channel= 1 qdr channel. This could accomodate well the 800 fsb need by modern P4. DDR appears around 2000 with the nforce1 chipset, the SIS735 and VIA kt 266. At this time, dual channel memory did not exist. The Athlon bus was running at 100 MHS, 200DDR on the first athlon thunderbird and at 133 MHz, 266 DDR on the trhunderbird "c" and newer Athlon XP. Before DDR, the fsb was running 2 times faster than the memory, creating latency, which was hurting performance. With DDR memory, that changed because the memory could work in sync with the FSB allowing much better performance. The P4 northwood "c" has a FSB of 800 MHZ while fastest official RAM available is pc 3200 (ddr 400, 200MHz clock). By doubling the bandwidth of the ram, and not its speed, the memory was able to perform on par with the P4's fsbm and that what put th northwood in front of the Athlon XP. Dual channel on AMD was not helping that much because the FSB is still 400 DDR so what that mean is that the bus was saturated and it give about 5-7% speed increase. What happended with AMD64, is that the memory controller is on the CPU's dye, which can be operated efficiently with lower latency than memory controller on the chipset. Plus, the short pipeline on the A64 make the need for bandwidth less important than the long pipeline on the P4, because, in case of branch misprediction, the entire pipeline has to be flushed and fill back again. When that happen on A64, since the pipeline is shorter, less data is needed to fill it back, but the data need to be sent fast, so the need for lower latency.
I have the Soltek k8an2e-gr which use the single channel socket 754. That doenst mean that it perform half of the socket 939, maybe only 5-7% slower. Remember, the fsb, on A64 is DDR400, which mean that the memory works in sync with the cpu.
So Zero1, before commenting on that, I suggest that you research a bit more about the intern of A64 CPU and P4 and about DDR memory. You will learn that DDR2, even if faster in term of datarate, will not works good as of yet on A64 because of its higher latency. When the DDR2 speed reach up to DDR667 or with latency down to resonable level for AMD 64, then it may become a viable option.
But stop saying that DDR memory cannot be run at its peak efficiency with only one stick..It can as it has been doing that since 2000. If you dont know "of NO way to-run as DDR not SD on a single ram chip" then you have a lot to learn and internet is a good place for that.
And "if you have any idea of how Rambus ram works(SAME as DDR) then you might know why it is NOT posiable to run on both peak and low clock pionts with one ram stick." yes I know how RAMBUS work, I did a fast explanation higher, and it is not the same as DDR...you appear to dont know, so a bit of researsh of your part could give you some clue
I dont means to be rude or impolite, but when peole says that I dont know something that I know, and keep giving misleading information, I just make sure that I put the thing straight back
I forgot to write that in order to acheive dual channel, you need 2 DDR memory stick performing the same(that why dual channel kit are available), as opposed to one or 2 mixed size for single channel