DDR3 or DDR2 System Memory?

[Ted Striker 338]

Hi guys, I've seen a lot of discussions on CPU speed, but couldn't find much on memory speed. I'm considering a Q6600, a P35 based Gigabyte or Asus motherboard, and a GTS8800 512. I'm hoping to overclock that chip to 3.6 mhz as I've seen reported by others on this forum. It appears that DDR2-800 should be a perfect fit for this. 400 FSB gets me 3.6 mhz on the CPU with its 9 multiplier and 800 mhz on the memory. However I've noticed that some are picking up DDR3 memory. Will lowering my CPU multiplier and running up the FSB to the higher mhz limits offered by DDR3 yield anything in FSX performance? This is an expensive propostion not only to purchase the DDR3 memory, but I'd also probably have to increase my motherboard costs to get an X38 based board. Anyone have any experience with a DDR2 to DDR3 upgrade with a FSB increase?I'm running 32 bit XP pro. Will I see any benefit getting 4gb of memory with this OS or should I stay with 2gb? Or does the performance benefit warrant getting Vista 64 bit to fully take advantage of 4gb of RAM. These are subjective questions so I guess what I'm really asking is what are the performance advantages of these options. Appreciate any feedback from anyone whose gone through these changes with FSX.Thanks,Ted

[sargeski 16]

> Appreciate any feedback from>anyone whose gone through these changes with FSX.The jump from DDR2 to DDR3 is not going to net you much of a performance increase. My recommendation would be to stick with the DDR2. Yes you will benefit from having greater than 2GB in 32 bit XP. You will just need to make the OS aware it. Many are reporting that they are running just fine on Vista 64. I myself am running on Vista 32.

[Guest Nick_N]

QX6700 7x510-530FSB (depending) @ DDR3 2000 8-8-9-22 @ 1T on the 333 CPU STRAP and DRAM sub timings tweaked8x500-520 if I crank up the chiller and rock the towerwould not fly FSX without it and I dont care what the benchmarks or silly hardware sites say, they are cluelessBut you wont be able to hit that FSB on a P35... probably 450-480 MAX on P35 but it will take the DDR3 modules as they are released. I am using DDR3 2000 engineering samples, love'emChoice is yours... buy it now or buy it later. You really think a next gen video card and system will like to play top dog at DDR2 800? Sure.. DDR2 will work OK.. but I am not restricted and do not have to go out and buy a DDR3 rig when the cards and proc's start cropping up at the end of the year that will use it even more efficiently. And in the mean time I dont have FSX problems and my sim is highly realsitic due to the resources it has to work with. its a question of economics, not performance.. and yes, FSX loves bandwidth.. from the CPU or the memory. Best to give it love from bothThere's the men http://www.xtremesystems.org/forums/showthread.php?p=2801797and then there's the boysQUOTE: DDR3 easily is 15-20 seconds faster clock for clock than DDR2 for Super Pi 32Mx38 is looking a bit better than x45 right now for FSB but I hear Intel is making some changes so thats and a few other things are coming up about mid-year. I would go x38 DDR3 if it were me.. or wait a few months more for the next round.If you don't know who Victor Wang is, you should.. he is the King of BIOS design and overclocksDDR3 must be clocked correctly and if done right it will wipe the pants off DDR2

[Guest D17S]

On the other hand, DDR3 is a hobbiest's passion, Only. FSX gameplay will Not benefit from higher memory bandwidths, nor will it benefit from a faster FSB. That's all great fun in the lab, 'cus that's where da big dogs live. Running maxed memory and FSB clock speed are mainly about braggin' rights 'mong the men. That's a terrific hobby and great fun. However, if just running FSX is your goal, stick with DDR2 for now. For a builder, project your final (hopeful) CPU target speed. Then calculate the FSB you will need to get there at your CPU's highest (or default) multiplier. Then buy DDR2 ram that can run twice that fast (DDR = Double the Data Rate of the FSB). That's it.Do Not drop your multiplier to run a faster FSB. Don't worry about about memory timings. Those strategies are useless away from the lab. Leave all that to the hobbiest (Of course, unless that's your hobby). Leave all that DDR3 stuff to the crazed, half-mad scientists . . . like me!Run your CPU at it Fastest stable Clock, with your FSB at its Lowest possible clock, and memory at 1:1 (DDR, ahhh, wouldn't that be 2:1?) with that FSB. ThaT is your max FSX performance strategy for we simple simmers.

[Guest Nick_N]

Hmmmm'Perhaps Phil Taylor was wrong?==============================================3) Current hardware and how to get the most from it There are several parts to the performance cost equation outside of the GPU. CPU, FSB speed, FSB ( Northbridge ) chipset, Memory Type, and Memory Perf are all valid parts of the cost equation on the CPU side. ********And memory OC'ing can give good perf wins***************.+++++++++++++++++++++++++++++++++++++++++++

[Guest Nick_N]

And I have to add one more thing to this onePlease, someone tell me at the end of the year, or even next year or the year after when the new system and proc

[Ted Striker 338]

Thanks for the responses everyone. I should have mentioned that while I have replaced components in computers with no problem, this will be my first build and I have not overclocked before. This machine will be for FSX only.To summarize the comments above, it sounds like DDR3-800 will not provide any performance improvement over DDR2-800 in a Q6600 & 8800GTS system running with a 400 FSB. However putting in 4gb instead of 2 gb of RAM will be beneficial. Is this correct?What I am also hearing is that lowering the CPU multiplier and runing up the FSB to utilize 1066 mhz memory ( whether it be DDR2 or DDR3 ) to achieve the same 3.6 ghz CPU speed will not give me a noticable improvement in FSX peformance. This tells me that the memory or FSB is not the bottleneck in the system above. Correct?The only reason I hear for going to DDR3 is to maximize the benefit of future components. So let's talk economics now. Currently I can purchase 4 mb of DDR2-1066 for $180, but 4 mb of DDR3-1066 will cost me $780. Either should equally handle a 500 mhz FSB just fine correct? I am planing on getting a good aftermarket air cooler, but I'm not planning on watercooling, chilling, or using cryogenics. So shouldn't a 500 FSB handle any CPU that Intel will be offering for the next year or two? I'm thinking that when I do need faster memory the price will have dropped significantly to where I may actually save by waiting.So I guess the real question is what future CPU and video card are going to require more than a 500 FSB and 1066 mhz memory assuming moderate overclocking with air cooling? When the models one step below the top of line versions of these are available, that seems to be when I will need DDR3.Thanks for the feedback and discussion guys. I apologize for my ignorance, my background is thermodynamics, not electrons and most of what I learned about computers and overclocking has been on this forum. So feel free to correct my analysis.Ted

[Guest Nick_N]

Hi TedI think you just answered your own question.. :)DDR3 is about massive memory bandwidth boosts which do in fact boost FSX. And its about a higher -stable- FSB, and, better CPU STRAP stability within a clock, and, a more stable clock in reference to memory sub timings, which most people are not into, aware of, and do not realize can and will boost FSX performance even further.800MHz DDR3 is (almost) the same as 800MHz DDR2. MHz is Mhz although there are other differences that make DDR3 more 'efficient' in calculations, those will not have the impact on FSX like raw MHz... therefore if you intend to remain in the range of DDR2's max limits, or under 600-650Mhz 'true' memory speed, then DDR3 is not for you. DDR3 does require the user to clock the system the same way you are suggesting you may clock DDR2, except, you would not purchase 800 (400Mhz) DDR3 memory or even 1333 (666.5 Mhz), you would purchase DDR3 1800-2000 (900-1000+MHz true speed) memory and it isnt cheap, especially 4 gigs.The issue is economics, not performance. As for nex gen.. All I can advise is make sure its a modern chipset motherboard. Most x38's and x45's will have support for newer proc's and will allow the benefit of the better cards.Yes, 4 gigs is an improvement with x32 or x64 OS but I would lean more toward the 64bit OS for that use if I was building from scratch. I moved to x64 several years ago and never went backYour original question was DDR2 or DDR3... the answer is if you are not willng to spend the money on the faster modules and clock the system for them, no its not worth it.

[Ted Striker 338]

Hi Nick,"Your original question was DDR2 or DDR3... the answer is if you are not willng to spend the money on the faster modules and clock the system for them, no its not worth it."Actually what I'm wondering is what FSX performance gain would I get from DDR3 over DDR2 if I did spend the money. My understanding is that with a Q6600 on air cooling, I would experience no performance gain with DDR3-2000 because the CPU would limit how high I could go with FSB assuming the memory and FSB clocks are 1:1.You are running your system at around 500 FSB. Are you running your memory at 1:1 with FSB or running the memory at a higher clock than the FSB?If the you are running your memory clock faster than the FSB, what benefits are you seeing in FSX? That's the basic question of my first post. I'm just trying to qualify/quantify the benefit. Then I can determine if the benefit is worth it. If you are running at 1:1 it seems that DDR2-1066 would offer the same FSX performance as you are currently getting with DDR3-2000 except for the future upgrading potential of the DDR3. Have I got this right or am I missing something?Appreciate you taking the time to discuss this Nick. Sure would be a lot easier if we were dicussing this over beers. :-beerchug Ted

[sargeski 16]

>Actually what I'm wondering is what FSX performance gain would>I get from DDR3 over DDR2 if I did spend the money.You will gain nothing of a noticeable difference performance wise on the rig you are planning on building. On the other hand, if your gonna get a tricked out water cooler or phase change cooler and overclock your PC to the hilt, you will see some performance benefit, but its not gonna be huge. In laymans terms the cost is not going to be worth the benefit at least not at this point in time.I took the $1200 plunge on DDR3 (us tech types just have to have the latest and greatest) and I wish I had went with DDR2 and saved quite a few dollars.

[Ted Striker 338]

Thanks Sargeski, that's the validation I was looking for.Ted

[Guest Nick_N]

4 gigs DDR3 on a P5k3 Deluxe?you are aware your memory is being retarded timing wise by populating 4 slots and you must be on the black slots for full operation with either 2 x1GB , or, 2x2GB and those 2GB sticks will not do DDR3 2000 not even close at decent timings, if what is available will do it at all.Also, P35 cant cut it against the x38The P5K3 and DDR3 was outrageous for the cost/performance ratio, it was the 'intro' DDR3 system released last May, I know, I tested it for Asus for 2 months from the end of March 07 to the end of May 07. Dumped in in October.So I am not sure exactly what you are running. I am not phase'd unless I want to play (dont use that for FSX) and I'll be darned if I will go back to DDR2 1066.If all 4 of those slots are populated on your board, or, you are running the 2x2GB slower sticks you did waste your money... known issue with the P5K3. Contact Asus, they will tell you the black slots are the only ones you can use for full speed DDR3 operation. Are the SuperTal memory modules the Z9's? If so with 2 you should be able to nail DDR3 1800 on decent timings as long as they are in the black slots only.If you have all 4 slots filled or 2x2GB, your better off on 2 1GB sticks and flooring it. If the ST modules are not the Z9's you will probably top out at about 1500-1600. Thats barely allowing better than DDR2 -unless- the sub timing is tweaked, DRAM STATIC READ is enabled and the trd adjust is enabled (Transaction Booster) on a decent FSB, then you should see a reasonable but not wild improvementI do agree, the P5K3 is not the DDR3 platform to use as a benchmark to compare and it was not worth the switch except to play..

[sargeski 16]

>4 gigs DDR3 on a P5k3 Deluxe?>>you are aware your memory is being retarded timing wise by>populating 4 slots and you must be on the black slots for full>operation with either 2 x1GB , or, 2x2GB and those 2GB sticks>will not do DDR3 2000 not even close at decent timings, if>what is available will do it at all.Yeah, I'm well aware of it Nick. I wasn't however when I first purchased everything. I'm running 4x1GB and let me tell you, it was a major pain in the arse getting the memory (all 4 1GB modules) running on this board (poor design and ASUS will blame it on the memory). It's pretty funny how easily the memory can be cranked up with only 2 lots populated (get your act together ASUS!).I was going to drop another $600 on 2x2GB Patriot Viper modules this weekend but bellied up at the last minute cause the original 4GB cost me $1200.I think I'm gonna wait till I upgrade the mobo. Any suggestions?BTW they are the Z9's rated at DDR3 1866

[Guest Nick_N]

The Z9's are the chips you want in that mobo, but only on the black slots.. all 4 are unstable if you try to clock. They designed it for low speed DDR3 and high speed and unfortunately you cant mix without accepting the lower timings and poor ratios even if you dont clock.Sorry you had that P5K3 experience.. I like to play too and I do get comp'd merchandise for testing... its really not a bad board but it does require a bit of TLC to get it to perform due to the fact that it was one of the first DDR3's on the market. I managed to get it to a constant 450FSB @ 3.6gig @ DDR3 1900 8-8-8-22 1T... purrred along and did not do a bad job in FSX (I thought it was still better than DDR2 in FSX at those speeds) but I was stuck at the 2GB limit if I wanted performance back then.There is a board coming up and going to be hitting the market in the next 8 weeks.. I cant say exactly when and I am not allowed to discuss.. but as soon as I catch wind of release I will post it to you.I hate to see a fellow tech in pain... Believe me, I understand.

[Guest Nick_N]

Ted, No I do not run 1:1thats not necessary with DDR3 and Intel.. the trick is nailing the right memory timings and sub timings in relation to the CPU STRAP, and the goal is to get what in known as the PERFORMANCE LEVEL down to a value of 6 or less.