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Discussion Starter #1
I'm stuck on choosing a processor, i have already bought my mobo and RAM, I've not overclocked before... but i shall now. I have found a couple of online suppliers in the UK for the opty 170, but I cant obtain the stepping from them. should i risk getting the 170 with unknown stepping or shall i dish out the extra £50 for the 4400?
 

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That's really a choice you have to make yourself, 50 pounds extra is quite a lot though. But from what I've seen there are no real "good" steppings on the Opterons like the single cores, they all hit around 2.7 with good cooling, and pretty much the same goes for the X2 4400+.
 

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Quote:


Originally Posted by elbrendo

and use the £50 towards a GTX

now you're thinking....170 all the way
 

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The architecture is exactly the same between Athlon 64's and 939-pin Opterons. The only difference is the amount of testing and validation that the chips pass through, so the reason some Opteron chips might overclock better is probably due to their being the most stable chips which AMD produced, were cherry picked and came through all the testing to become server/workstation chips.

Not to say that Athlon 64s are less than stable. They are extremely stable in my experience, at their rated speeds and with a solid motherboard. Opterons are just tested using very different workloads, since their intended purpose is different.

An Athlon 64 and Opteron which are both running at the same clock speed, have the same cache, use the same socket, and are the same chip revision, are the exact same chip.

Thus the Opterons have more headroom if you are going to overclock and will run cooler overclocked. They are for servers mainly, but they produce them in socket 939 so they can be used in a regular socket 939 board. You may have to flash your bios to get the board to recognise them as well. Also if you do not use them in a server recognised board you void the warranty but for the most who have purchased them for desktop use will be overclocking as well so the warranty is rather a moot point.

R
 

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Discussion Starter #6
Thanks for the help ropey,

This is going off my original subject but, you have PC4000 RAM, why/how do you use it? with an amd processor that is 'supposed' to be only compatible with PC3200? is this because you underclock your ram from the start to DDR400 speeds??
 

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Quote:


Originally Posted by elbrendo

Thanks for the help ropey,

This is going off my original subject but, you have PC4000 RAM, why/how do you use it? with an amd processor that is 'supposed' to be only compatible with PC3200? is this because you underclock your ram from the start to DDR400 speeds??

You overclock by raising your FSB. The memory speed is determined by doubleing the FSB. So your default is 200Mhz FSB, but you get 400Mhz RAM cuz its DDR. When you overclock the FSB to, say, 225Mhz, the RAM becomes DDR 500 (PC4000). If the RAM is rated for that speed, you know you will be stable. If you were to buy PC3200 (DDR400) then there is no guarentee your RAM will be able to hold that speed. This if just a basic explanation, there is all sorts of other stuff like dividers and timings that also affect RAM performance.
 

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Quote:


Originally Posted by elbrendo

Thanks for the help ropey,

This is going off my original subject but, you have PC4000 RAM, why/how do you use it? with an amd processor that is 'supposed' to be only compatible with PC3200? is this because you underclock your ram from the start to DDR400 speeds??

DDR400 or PC3200 is the highest Jedec recognised RAM speed.

To run PC4000 is just the same as running your PC3200 at say 210MHz which is 10MHz over it's 200MHz rating hence the DDR400 (which is 2x200MHz).

By utilising RAM modules with higher rated speeds you have the ability to be able to run high fsb's and tight timmings than the lower rated ones which may top out at 2545MHz. TCCD is most surely, along with BH-5 ( lots of voltage to work, upwards of +3.3V) the best DDR400 RAM you can get.

cheers
 

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Yeah, I understand, putting in DDR500 is a more likley choice to have a higher fsb etc etc blah blah. i think my question has not been understood... I want to know how to get DDR500 to work with my motherboard (which is advertised as a DDR400 motherboard)? If the DDR500 just "does" work, why dont they advertise my mobo as a DDR500 compatible motherboard? and not a DDR400 one? ...phew
 

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The mobos only say they are compatible with PC3200 RAM because it is, like the reply from above, the highest approved rating from JEDEC. The mobo manufacturers can only state the highest approved rating but that doesn't mean you cannot use faster RAM. Since all mobos are default to 200 mhz for the fsb, all you have to do is crank that up to the speed of the faster RAM (or even faster if you OC it). It's just like putting DDR400 RAM in older mobos that were only designed for slower RAM, ie. PC2100 (133mhz). The mobo won't recognize that the RAM you put in is DDR400 but you can safely crank up the fsb knowing that your RAM is not going to limit you in your OC.
 

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yep, that is exactly how it works, I just thought I'd give a couple examples.

I just recently bought a sick of DDR400 notebook SODIMM memory for my wife's laptop and installed it in her computer. However, her computer only lists that it is compatable with PC2100 or DDR266. So basically what happens is all DDR memory is backwards compatable... so you can put DDR400 in a DDR333 motherboard and the RAM will run at DDR333... If however, you choose to overclock it will give you more headroom to do so... while you will be overclocking your cpu and motherboard (fsb) your RAM won't be overclocked until you have hit the DDR400 range (fsb or htt of 200)

So, now to your situation. all A64 socket 939 motherboards support DDR400 because the htt is 200. To overclock your cpu you raise the htt... which overclocks your memory as well. This is where having DDR500 will come in handy. You are guaranteed that your memory will work at a htt of 250 where with most DDR400 you are not and it's just luck of the draw... and informed purchasing.

So, when looking at your configuration it would be good for you to get some DDR500 or some RAM that uses TCCD chips. Your motherboard can't supply more than 3.0v to the RAM so Samsung TCCD will be your best bet for RAM.

What model Corsair RAM do you have? from there we can figure out what IC's your RAM uses and give you a rough estimate about what it will do in regards to overclocking and what timings/voltages it will take to get there.

oh, and the opty 165's have been hitting about 2.8Ghz... so I would assume the 170 would be able to get about there too...

You may not be able to get the highest oc w/ that board as you will probably be limited to 1.55v for the cpu and you cannot increase voltage on the chipset... Also, you will not be able to run a 1T command rate on your RAM past a htt of 240... all that said, your board is fairly easy to OC and makes a great board to learn how to OC on. You can also get pretty decent overclocks with some patience.

I'm familar w/ that board so when you get everything together and are ready to OC let me know and I might be able to help you out.
 

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well very few of the 3200C2 use TCCD. the next best use TCC5, and after that they're just kinda ehh...
if you look on your sticker you can find what revision number you have... that's what you'll need to tell what specific IC's your RAM uses... Corsair has used several different IC's for their C2 RAM.
you can take a look here and see if you can find your RAM
http://www.houseofhelp.com/forums/sh...ad.php?t=44365

just a word of caution...
I had a pair of that same exact RAM and it would not run at a 1T command rate even at DDR400 speeds... I RMA'd it and the pair I got only worked for less than 24 hours... I sent them back to Corsair. The 3rd pair work just fine but the RAM Guy refused to tell me what IC's they use... He's a real _____ I'll let you fill in the blank, but know that it's not suitable for here...

So anywho, most C2 will OC to around 240. Some will make it to DDR500 but I personally wouldn't hold my breath if I were you... and to get them to do DDR500 or close you'll have to loosen the timings to about 3-3-3-8 which is absolute crap.
 

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Sorry, slightly off topic, but brendo where did you find optys in the UK that are actually available, have been to loads of sites, but all out of stock, or not listing them at all.
 

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Discussion Starter #17
Quote:


Originally Posted by chrisjmoss

Sorry, slightly off topic, but brendo where did you find optys in the UK that are actually available, have been to loads of sites, but all out of stock, or not listing them at all.

you wanted to know where i'm getting my opty from...

http://www.techstore.co.uk/browse.ph...odLineID=67467

They're not getting them in stock for another 2 weeks unfortunatly.
 
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