Avoiding Bottlenecks W/ Dual Channel Memory Witnessing a PCs Potential

[AllfatherBlack 0]

Im sure most of us that read these boards are absolute computer geniuses. Ive mentioned in some of my posts that it seems like everyones a computer tech these days. Well thats not going to stop me from, hopefully, contributing to the knowledge of others. Here are some quick tips on preventing bottlenecks, common with p4's, broken down for the lay user.Quick Quickie: Intels VS AMDsI am not about to voice my part on a battle thats been waged for quite sometime now between two companies that could have just as easily ended up one, big company ( referring to the fact that AMD almost worked with Intel to manufacture chips ). I just want to point out for those who dont know the subtle difference in the technologies. Quickly quick-like, Intel and AMD cpus handle instructions per clock cycle differently ( how many computations they complete on a clock cycle ). Intel uses tech that peforms 4 functions per clock ( note this is a very simple way of putting it that may not be worded correctly, so please feel free to fix any glaring inconsitencys ) whereas AMD ( like DDR RAM ) performs 2. It would seem AMD is half as fast as Intel but thats not true. AMD handles a heavier ( for lack of a better word ) load on its 2 than INtel handles on its 4. Ultimately ( note HEAVY ABRIDGEMENTS ), this results in AMD single functions ( having one application open ) peforming faster than Intels single functions, and the INtel performing better when multi-tasking ( usually medium to heavy multitasking ). Please read up on the subject as I by no means IN ANY WAY am beginning to cover how this works. I just wanted to support my thesis with a little explanation. BottleneckingBottlenecking is a problem best explained using RAM, I think. Most of us have dealt with RAM atleast once, and if you havent, this may not be the best explanation and Im sorry. But I digress. Most of us know that if we buy RAM that is faster than our motherboard can handle, we can still use the RAM, but it will run slower than intended. This is bad example of a motherboard bottlenecking RAM; the RAM can do more but wont because the motherboard only allows it to do so much. This is a poor example of bottlenecking. The bottlenecking we are going to be discussing pertains to mostly P4s, and data transfer between RAM and CPU. For a PC to reach its potential, the CPU and RAM must have the same thoroughput.In order to see the true data transfer potential ( aka thoroughput ) of your CPU, multiply the front side bus speed ( commonly 533mhz, 800mhz, or the new 1066mhz for Pentiums ) by 64 then divide it by 8 ( to find ANYTHINGS thoroughput, use this formula; REAL Clock Speed x Instructions Per Cycle x 64 / 8 ). An 800mhz FSB, multiplied by 64 and divided by 8 is 6400, meaning the thoroughput is 6,400 Mbps. If you have a P4 2.8ghz with an 800mhz FSB ( like me ) your thoroughput is 6400 Mbps, and your RAM should have the same. MY motherboard only supports up to DDR400 ( PC3200 ) RAM. To find my RAMs thoroughput, we multiply the REAL clock speed ( which is 200mhz, or 400mhz considering its doing 2 instructions per cycle ) by number of instuctions per cycle ( 2 ) by 64 then divide it by 8, which equals 3200 Mbps. Those in the now or those who have eyes will see that the PC rating matches the thoroughput. That because thats what its for, telling you the thoroughput and saving you time.As you can see my RAM is capable of HALF the thoroughput my CPU is, meaning I will only ever see half my computers potential. Fortunetly, Dual Channel memory allows one to DOUBLE the thoroughput of their RAM by installing 2 near identical ( identical strongly suggested ) sticks of RAM, or COAST ( cache on a stick ), into the 1st and 3rd memory slot (1st and second if you only have two, may be different depending on the motherboard ). Your motherboard must be dual channel capable to support this feature. Newer AMDs contain the memory controller ( which is what actually decides whether or not you can use dual channel ) on the CPU, so with newer AMDs, the CPU actually decides whether or not you can use dual channel. If you can use it, USE IT. The difference will be noticeable, and thats all that matters right?Simply use this equation to match your CPUs thoroughput to the RAMs thoroughput, preventing the most common bottleneck ( especially in P4s! Intel should be slapped for crippling themselves with industry standard tech );REAL Clock Speed x Number of Instructions x 64 / 8 = ( thoroughput )Cheat Sheet: Pentiums use 4 instructions, AMDs use 2, DDR memory uses 2 and SDRAM uses 1. The clock speed on DDR memory is TWICE the REAL clock speed ( hence DOUBLE data rate ), and the clock speed rfers to the front side bus speed when referring to CPUs.I hope this helps loosen up all those crippled P4s out there. Hell, I hope this helps just one person, so itll be worth while when I inevitably get reamed for being the wrongest person ever.

[moogie 0]

I read your "rant" LOL in another area, complaining that no one has replied to this particular posting of yours, so I thought I'd come here and read it.I think you've explained the in's and out's of RAM, and dual channel memory in particular, very well. And, you've explained it so that those who are not quite as up on tech terms and hardware can still follow what you're saying. Well done!I'm not going to comment on Intel vs AMD. I'm a long standing Intel fan and it would take a lot of convincing to make me change!

[ameribass 0]

Thanks a lot for the interesting read! I am sure that I, and mostly everyone else that reads this, will find this inforamtion very useful in the future. Thanks a lot for the post once again and I hope to see more quality posts like this one in the near future. See ya later!

[AllfatherBlack 0]

I would like to thank all the people who humored me and responded to this stupid post :)Now to post some more stupid stuff! Its what I do best!