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Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
Somebodys gotta give me a DDR 101 guide or lesson on RAM.. I dunno anything about all the latencies and other stuff I should be looking at before buying DDR ram..
I'm getting my 754 board soon and I dunno what RAM to buy with it..Could someone give me a link to a guide or somethin please? :rolleyes:
 

c627627

c(n*199780) Senior Member
Joined
Feb 18, 2002
Welcome to the forums, Sa3atsky.

Here's some general info for you:
http://www.c627627.com/RAM/
http://www.c627627.com/AMD/Athlon64/

You'll want DDR I RAM capable of running at least PC3200 speeds for socket 754.

I don't know what the current hot deal is (they change all the time, try memory section maybe)

In the old days, you could use PC2100 RAM and PC2700 for socket A CPUs like these:
http://www.c627627.com/AMD/AthlonXP/

I have the old socket so I can use the old inexpensive PC2700 RAM which set to:

T(RAS) 6
T(RCD) 3
T(RP) 3
CAS 2.5


CAS Latency is most important for memory bandwidth. Set it to 2 whenever possible. In my case I can only overclock with it set to 2.5, if I set it to 2 I can't overclock the FSB much at all.

2nd important is (Trcd). It is the number of cycles between the row and column access. 2 is good,
but 3 is OK.

(Trp) is the precharge time after an active access. 2 is good, but 3 is OK.

Active to Precharge Delay (Tras) is the minimum time for an active access (to perform a single
row and column access).
It is the least importance for memory performance. Smaller the better. Usually 5 or 6 or 7 is fine.
Tras >= Trcd + CAS

Sometimes there's also Cmd Rate. 1T is better than 2T
 

Docta_Z

Member
Joined
Aug 6, 2002
Location
Canada
Nice job on the explaination c627627!

c627627 said:
Tras >= Trcd + CAS

Just a note: I've read different opinions on this and occassionally I find the advice to be (I believe this is Corsair's) RAS = Trcd + CAS + 2 (for optimal stability I believe :))

Just a thought though. Good luck and welcome to the forums. :)
 
OP
Sa3atsky

Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
What are my choices? I mean brand-wise, model-wise? OCZ, Corsair and Kingston are good RAM manufacturers I hear
 
OP
Sa3atsky

Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
memory @ 1:1 248x2 = 498 mhz - 2.85v
1t 3-2-2-10 timings
Heres an example of when someones talkin about RAM.. could you please explain to me this terminology in more detail
I seem to be getting the hang of this RAM deal..... Just need the proper guidance
 
OP
Sa3atsky

Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
okay Ive read some more.. so now I know what numbers mean good RAM... 2 questions

1) Whats sync and async?
2) Whats are the best overclockable sticks of ram right now? (I'm aiming at *2 512mb) for socket 754, so no dual-channel bs ;)
 
OP
Sa3atsky

Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
Hey, and I'm reading in OCZ specs "CL 3-4-4-8".. whats CL? and wheres the Cmd rate?

AND, what speeds should I be looking at?
 

Docta_Z

Member
Joined
Aug 6, 2002
Location
Canada
For a 64 bit system - you probably want to stick to low latency PC3200.

If it's a dual set of ram, chances are CMD rate is 2t.

I would buy OCZ ram - why?

#1 They have the most reputable overclocking ram on the market today
#2 Their ram is fairly moderately priced
#3 Their RMA department is amazing if you ever have a problem and their customer support is unreal.
#4 They support (and basically cater to) overclocking your ram! :attn:
 
OP
Sa3atsky

Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
DUDE! :) These OCZ guys rock!
Low latency PC3200's huh? why not PC3700's?

So lets say I'm getting "2x 512mb OCZ 3700 EB Platinum Edition", good enough? do they really cost $350? I'm buying them from a canadian dealer, are they too much?

Comeon all you overclockers out there..tell me what RAM you have..guide me!
 

Docta_Z

Member
Joined
Aug 6, 2002
Location
Canada
If you're buying a Amd 64 bit system - you may want to read the AMD64 101 post.

Because of the onboard memory controller, it is far more important to get ram that has low lat then to get ram that runs at a faster speed with amd 64 chips...
 
OP
Sa3atsky

Sa3atsky

Member
Joined
Jul 11, 2004
Location
Bahrain
Yeah, I read that... but are the OCZ EB Platinum Edition's best for low-latency? Or is there better? Its just coz I dont get the "CL 2.5-3-2-8" in the specs.. I remember I read that CL 2 beats CL 2.5 but I'm not sure what it means..

I'm just looking for the most stable lowest latency bestest :) RAM for overclocking a socket 754 Clawhammer that costs about $250 - $265 tops