Totally lost

mrt88

mrt88

mrt88

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Joined
8 Jul 2008
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120
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Uk
Hey all
Im ordering the parts for my first ever build this week and im at a total loss when it coems to what ram.
I’m looking for 4gb of ddr2 to go with a p5q deluxe and a q9550
I’m trying to keep costs down but im lost when it comes to deciding between 800, 1000, 1600 mhz
If anyone could recommend me some good ram at the lower end of the price scale then it would be a great help
Thanks all
 
Heya, this used to confuse the hell out of me but think I have it sorted now.

Basically it really depends on how much overclocking you will be doing, as the CPU has an FSB of 1333, now from what I understand is, that you divide this number by 4 to get 333.

Now to get the correct RAM you need to divide it by 2 soo 800 becomes 400 etc.

So if you don't plan on overclocking at just use at stock speeds you only need 667 (PC2-5300) as 667/2=333.

But again it depends on overclocking, personally I would choose a fast set of 800 (PC2-6400) and overclock a little or 1000 and overclock a bit more.
 
depends on how much you want to overclock...

good PC6400 should do 450 FSB.. which on a Q9550 would give you a maxium overclock of 450*8.5= 3.825ghz

PC8500 should be good for 533FSB @ its rated timmings and therefore would allow you to clock higher... or it would allow you to run at higher dividers (where you run the RAM faster than the FSB)
 
Hi I'm really new to this as well so I have quick question.

Do you generally aim for 1:1 ratio between FSB and DRAM?
 
thanks for the replys so far, dont plan on clocking any time soon. got about £50-60 to play with, any recommendations ?
 
Well would normally recommend 2*2gb but as you have an Asus board they cope very well with all 4 slots being used so you might consider two sets of this.. had 4 * 1gb of this in an older Asus board and done 900mhz (450FBS) @ 4-4-4-12

alternativily if you are looking to buy more RAM in the future and want some spare slots you could get this.. a bit more pricey though
 
8500 will be your best bet as its quicker and will be able to handle a bigger overclock without adjusting the timings to much but also keeping the 1.1 divider that makes an overclock better
 
Sundance said:
Hi I'm really new to this as well so I have quick question.

Do you generally aim for 1:1 ratio between FSB and DRAM?
Click to expand...

You can but generally you choose the RAM that best suits your memory.

For example, an FSB of 266MHz with PC6400 on a 1:1 ratio, the memory would run at 532Mhz .. a long way short of the quote 800MHz it's capable of.

However, having setting the divider to 2:3 would mean the FSBb would continue to run at 266MHZ but the memory would be asyncrounously running at near 800MHz.

i.e. 532 / 2 * 3


This may help you understand better :

http://www.huddysworld.co.uk/Techpages/PCZone_TechieTalk_1.shtml
 
Thanks Huddy,

So would I be right in saying; is a E8400 at 3.6GHz (9*400), with PC2 6400 RAM at 800 MHz at a 1:1 FSB ratio?

Is there any benefit of increasing the RAM speed above this?

Thanks
 
Sundance said:
Thanks Huddy,

So would I be right in saying; is a E8400 at 3.6GHz (9*400), with PC2 6400 RAM at 800 MHz at a 1:1 FSB ratio?

Is there any benefit of increasing the RAM speed above this?

Thanks
Click to expand...

Yep, that's exactly what I am running. Makes me wish I had gone for the faster RAM though because I know the CPU has more to give :)
 
Basically if you are overclocking, then buy the PC8500. Unless you are into extreme overclocking you will not need any more headroom. The prices are close enough though that it is worth the extra £10-£20.
 
by the sounds of it hes not going to over clock though so might as well jus stick with some cas4 800mhz
 
Sundance said:
Thanks Huddy,

So would I be right in saying; is a E8400 at 3.6GHz (9*400), with PC2 6400 RAM at 800 MHz at a 1:1 FSB ratio?

Is there any benefit of increasing the RAM speed above this?

Thanks
Click to expand...


Yes and Yes, although cooling your chipset my become a problem :)

However, depending on the PC6400 you buy, you might get beyond 800MHz and even to 900MHz which is considered a memory OC.
 
So just to jump in on this thread and after your reading your great writeup there Huddy, Im planning on an 8400C2D and PC6400RAM (800mhz)

how much overclocking headroom does that ram give me with that chip then? I'm not planning on breaking records with this rig but wouldn't want to be held back by the RAM, but annoyingly gota build this rig on a budget! The way I see it is that ram will oc by quiet a bit hopefully, enough to stretch out the CPU enough?
 
Depends if it is CAS 4 or CAS 5. CAS 4 should do over 900mhz (simply because you can drop it down to CAS 5 when CAS 4 hits its wall). CAS 5 PC6400 won't clock as far.
 
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