Cas vs. Speed? what about Voltage

Building a new rig and i am not sure what the best path to go is when it comes to ram.

MB: MSI 790FX-GD70 AM3 AMD 790FX
CPU: Phenom 2 x3 720 BE

Question 1: If i get ram that is at speeds of 1600 but a voltage of 1.5, will i have to increase that voltage regardless so it can operated at 1600 with its 9 cas latency?

I am aware that there is a AMD cpu limitation here on ram operating at 1600. Ware i get confused is the recommended voltage for ram on this MB is 1.5v but in MSI' tested ram support list in the 1600 overclocking table most if not all of the ram is 1.65v. Hence my question if i get 1600 ram at 1.5v CAN it operate at its stock speed and latency without adding voltage; without overcloking? Or will it auto adjust to 1333 or 1066 with a different cas latency entill i adjust the setting in the bios, hence having to overclock to get the ram to work at its stock timings?

Question 2: After reading the review on this site about cas latency and speed i was still a little confused because it did not include info on different voltage settings. If in the future i would like to overclock to a moderate or medium level would it still be ok to get a ripjaw series of ram that is 1.5 1333 but with a 7 cas latency? I know that in the beginning i would not need to overclock to achieve those timings but in the future when i start overclocking would it be better to already have ram that is manufactured at 1600 for a moderate overclock or would the 1333 be fine? Then when i really want to oc i would just buy some new stuff at 1866+? Maybe more money that way, and thats kinda my dilemma with different ram modulus offering more then one speed and latency setting would it be more economical to get a set of 1600 ram at 1.5v? The 1600 is on the tested support list but the 1333 is not. Which brings me to another dilemma why does the support list say PC11000 ddr3 1333? all the 1333 ram on newegg is PC10600,10660,and 10666?

This brings me to the dilemma of choosing a AMD build. There is only a few sets of dual channel ddr3 ram the states it was specifically made for an AMD system but the exact opposite occurs for for Intel's p55 and x58 chipset. I did find one set specifically made for AMD 790FX but it has a voltage of 1.65 and a speed of 1600 cas 8. Meaning i would have to oc out of the gate. Not i bad thing i guess. or i could just let it auto adjust to whatever timmings it use's at 1.5v.

Needles to say there should not be in the begging to much of a noticeable performance difference between 1333c7 1.5v and 1600c9 1.5v, maybe the answer is to go with OCZ with a cas of 8 despite the1.65v.
I dont know enought about ovclocking yet to understand the fundementals of voltage settings.

some advice would be greatly appreciated.

VGA: MSI R5750-PM2D1G Radeon HD 5750 1GB
Case:Thermaltake Xaser VI Black
PWS: Corsair 550w

P.S on another note if i am spending 1030$CAD on a system, is AMD the way to go? I like the ability MSI has to unlock the 4th core of a 3core cpu. and i like the 16x + 16x or 4 way CFx on 8x+8x+8x+8x, not heard of for 180$ in an Intel system. You pay 350$+ for that setup on the x58 chipset, p55 is mostly limited to 16x + 4x and only a few have 3 way no 4 way. Not like to many ppl will use 4 way but still this is the only board with the 790FX Chip for that price. I have made hypothetical p55 and x58 builds in the past but i always think that you get more bang for your buck, going with the AMD system. the real world difference between a i7 and a Phenom shouldn't be that noticeable, especially important because Intel is a lot more money.

This is the first time i am going to be building a computer so people who have built a few your experience would come in handy especially if you have built both AMD and INTEL.
Again some advice would be greatly appreciated.
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More about speed voltage
  1. Question 1: You should be able to run that ram at 1600 and 1.5V, but the information is a little vague from newegg. I noticed on the side of the memory module the sticker says 1.5-1.6V. You might need to bump it up to 1.6 or even 1.65V if you run into errors at 1600. These voltages are safe. Go to the manufacturers website to get better info.

    Question 2:Real world difference between ddr3 1333 and 1600 is very small and probably impossible to perceive outside of benchmarks. If you buy 1600 modules you can easily run them at 1333 with tighter timings. This will give you headroom in the future if you want to overclock. An article here showed that games actually preferred 1333 with tight timings over 1600.

    With a radeon 5750, I would go the AMD route. These days with quad cores at 3+ GHz it's the gpu that is the bottleneck. You could save money with a phenom ii and keep the left over cash to crossfire with another 5750. I would stay away from a 16x + 4x crossfire board and get one with at least 8x+8x if not 16x+16x if you plan on going the crossfire route.

    With a 5750, you aren't a hardcore gamer, so I would not waste money on intel. But that is just my opinion and you should get some other opinions before making a decision. I hope this helps you some.
  2. i will definetly go to AMD Cause the following 3 reasons:

    #1: Technology step up very 3 to 6 months (im talking big leaps) so what you expend on hardware it will be devaluated by the time passes.

    #2: when you inevest on AMD you get a close performance to intel so far there is no software aside benchmarking tools that can handle the power of today hardware if you say intel is more "future proof" let me tell you then by the time software catch up with the hardware capability your build will not be any apealing to you cause you gonna want the new stuff (if you are an enthusiast like me)

    #3: AMD is way Cheaper then intel (and im talking Big bucks here). it gives you a good taste of the new technology for a very afordable price that gives you more headroom to get other stuff like a better case a gaming mouse & keyboard, LCD gadgets for you case maybe some nice cpu fan better GFX good web cam or a bigger 1080p monitor etc.. etc.. and make your cpu to look and be very cool!

    Sidenote: i build like 5 computer so far all of them for personal use i expend thousads of dollars on my frist one (it was really good) but it went really old after 2 years (at least on my eyes ) now i have a very nice build at good price asus M4a79T deluxe 790fx chipset quad crossfire , 6 gigs ddr3 kingston and a dual core Phenom 2 550 Black edition unlocked to Quadcore at 3.6 ghz and stable! for $ i care more on other stuff like how my computer looks and feels, you gotta love ergonomic keyboards fast response monitors and heat sensors that look so cool and have a pwerfull enough cpu to handle anythin that i want.
    well those are my 2 cents but if you have the money Go for the best Wich on the hardware side it doesnt last long.
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