Which RAM should I buy ?

Status
Not open for further replies.

imjimmy

Broken In
The Kingston KVR PC3200(DDR 400) that i have found- come sealed in a pack with a kingston seal. Also there is a white colour sticker on the RAM saying KVRx64AC3/512- giving the model number, Serial no etc etc..

However when u look at the actual RAM chip..it's by Hynix..I mean Hynix D43 is written etc..?

Why is that.. Is Kingston KVR rebadged Hynix? Or is this fake Kingston floating around in the market?
 

rohanbee

Padawan
Funny but i checked my kingston and it does not say hynix................ i think i will re-check. Hynix does supply to a lot of memory manufacturers though.
 

drvarunmehta

Wise Old Owl
akshayt said:
Just bought 512mb ddr 400 hynix d43 for 3025 each
bought 2

ram timing default- 3 4 4 8
also,in ut04 and chronciles of riddick it was a bit slow today
why so?

brand name of ram is not written in cpuz

are they genuine?
I got 2x512 mb Transcend DDR400 running at 3 3 3 8 for 4500 just 2 weeks ago. I think you paid too much for 512 mb hynix
 
OP
A

akshayt

Wise Old Owl
which mobo do you have
also transcend in delhi from media man for 2750 + tax per module

did you get box packed, there are/were fake transcends too

check with cpu-z for manufacturer name

my manufacturer if 000000 ,actually a number of 0s , maybe more than the abv figure
everst ,giving serial as none
 

AlienTech

In the zone
very good explanation here on RAM timings...

RAM Timings/options

Key


*Star= slight influence Bandwith
**Star= Very influential Bandwith
star*= Slight influence stablity
Star**= Very influential Stabilty
*star*= Sligth influence in both stabilty and bandwith
**Star**= Very infuential in both stability and Bandwith

DRAM Timings

**Dram Frequency Set(Mhz)**= 100(Mhz)(1/02), 120(Mhz)(3/05), 133(Mhz)(2/03), 140(Mhz)(7/10), 150(Mhz)(3/04), 166(Mhz)(5/06), 180(Mhz)(9/10), 200(Mhz)(1/01).

This option sets the Dram ratio. with a64, the ratios are not always writen in stone, for example 166(5/06) isnt always 5/6 ratio. you can refer to this chart for the exact ratios(they may not all be right, and thanks to Oskar_WU for his help with the chart)

**Command Per Clock(CPC)**= Auto, Enable(1T), Disable(2T), this is also called Command rate.

It is best, in most cases to use Disable(2T) with 2x1gig, 2x512, or 1x1gig Ram modules for the best stablility. 1T yeilds better performance, and 2T usually yeilds the best stabilty/overclock

PLEASE NOTE THAT IF YOU ARE USING A "CO" REV. CPU THIS OPTION(CPC) WILL NOT APPEAR IN BIOS. THIS IS BECAUSE "CO" REV. CPU'S DO NOT SUPPORT 2T TIMING, ONLY 1T. IF YOU HAVE A "CG" REV. CPU, YOU WILL BE ABLE TO SELECT EITHER AUTO, 1T, OR 2T.

*Cas Latency Control(tCL)**= 1, 1.5, 2, 2.5 3, 3.5, 4, 4.5. I would suggest only using, 2, 2.5, and 3..

This is the first timing that most ram companies rate there ram with. For example, you might see ram rated at 3-4-4-8@275mhz. this is the 3, in than situation.

2 yeilds the best performance, but, unless you have either Winbond BH-5, or BH-6, it is unlikely you will beable to reach you maximum overclock at CAS2. CAS3 is usually yeilds the best stablility/overclock.

PLEASE NOTE, IF YOU HAVE WB-BH-5/6, YOU MOST LIKELY WILL NOT BE ABLE TO USE CAS3, AND SOME MAY NOT BE ABLE TO USE CAS2.5, MY BH-6 WILL NOT POST AT CAS2.5, OR CAS3, IT WILL ONLY POST AT CAS2.

**RAS# to CAS# delay(tRCD)**= 0, 1, 2, 3, 4, 5, 6, 7. I would suggest only using 2-5

This is the second timing that most ram companies rate there ram with. For example, you might see ram rated at 3-4-4-8@275mhz. this is the 4, in than situation.

2 yeilds the best performance, and 4-5(5 is usually overkill) yeilds the best overclock. Most rams will not be able to use 2, and reach there max OC.


*Min RAS# active timing(tRAS)*= 00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 10, 11, 12, 13, 14, 15.

This is the forth timing that most ram companies rate there ram with. For example, you might see ram rated at 3-4-4-8@275mhz. this is the 8, in than situation.

This is a very debated timing. Some may argue that 00, 05, or 10 is the faster/most stable. but i really think there isnt a right anwser for this one, it all depends on your ram. But, if you need a good starting point, usually most/all rams can accieve there max OC on 10 tRAS, even if one of the other setting is faster.


**Row Precharge timing(tRP)**= 0,1, 2, 3, 4, 5, 6, 7. I would suggest using only 2-5.

This is the third timing that most ram companies rate there ram with. For example, you might see ram rated at 3-4-4-8@275mhz. this is the 4, in than situation.


2 yeilds the best performance, and 4-5(5 is usually overkill) yeilds the best overclock. Most rams will not be able to use 2, and reach there max OC

**Row Cycle Time(tRC)**= 7-22 in 1.0 increments.

7 yeilds the best performance, 15-17(i think 17 is overkill) yeilds the best stability/overclock. i would start at 15, and work your way down from there. Also, 7 is usually much to tight, for most ram.

**Row Refresh cyc time(tRFC)**= 9-24 in 1.0 increments.

this timing is usually always set to 2-4 clocks higher that the tRC.

10 yields the best performance(well 9 would, but 9 is to tight), and 17-19(i think 19 is overkill) yields the best stabiltiy/overclock. i i would start at 17 and work your way down

*Row to Row Delay(also called Ras to Ras delay)(tRRD)*= 0-7 in 1.0 increments.

00, or 2 seems to yields the best performance, and 4-6 yeilds the best stabiltity/overclock. i know that 00 sounds odd, but it works great for me, even at 260mhz

*Write Recovery Time(tWR)*= 2, 3

2 yeilds better perfomance, and 3 yields better stability/overclock.

*Write to read Delay(tWTR)*= 1, 2.

1 yeilds better perfomance, and 2 yields better stability/overclock.

*Read to Write delay(tRTW)*= 1-8 in 1.0 increments.

1 yeilds better perfomance, and 4(i think any above 4 is overkill) yields better stability/overclock.


*www.ocforums.com/showthread.php?t=329627

Another thing I noticed, My 256MB ram is PC2100 DDR-266 and my 512MB ram is PC3200 DDR-400. Both are J chips. Yet they are both using the same timings (the J's and D43). The bandwidth difference is almost double. The J's are not even specied ot run @ 400MZH. But the D43 DDR-400 are run @ 3-3-3. IE The J's are not designed to run @ CL3 only the D43's are. I suspect they are overclocking the chips. But these was sealed packages from Simmtronics USA.

*www.hynix.com/datasheet/eng/dram/details/dram_02_HY5DU56822AT.jsp
 

AlienTech

In the zone
akshayt said:
with cpu x ram timings are 3-4-4-8 then maybe 12-16
no brand name of ram in cpu z

Only the HY5DU56822AT -D4 - 200MHz DDR400 (3-4-4) can run @ 3-4-4, the HY5DU56822AT -D43 - 200MHz DDR400 (3-3-3) run @ 3-3-3.

*www.hynix.com/datasheet/eng/dram/details/dram_02_HY5DU56822AT.jsp

I have to study the spcs to figure this out, been out of the technical loop for too long now *www.hynix.com/datasheet/pdf/dram/HY5DU564(8,16)22A(L)T(Rev0.4).pdf
 

rohanbee

Padawan
Thanks alientech good and easy to understand explanation of ram and its timmings! Cleared quite a few doubts.
 

AlienTech

In the zone
DRAM control (A-B-C-D numbering) Percent Change
(A)CAS (2 to 2.5) -0.89%
(B)TRCD (2 to 3) -3.5%
(C)TRP (2 to 3) -2.29%
(D)TRAS (5 to 6) 0.21% (Should be (A) CAS latency + (B) TRCD + 2 cycles)
Command rate (CR: 1T to 2T) -2.68%
Change all at once -5.38%

The changes are all in the direction you would expect except for TRAS. In their order of importance is TRCD => CR => TRP => CAS => TRAS. Also, the total effect of changing all settings at once is not the sum of the individual settings and is on the order of 5.5%. Thus you see a 5.5% improvement in system performance between the less aggressive memory settings to the most aggressive.

For example, the most aggressive memory timing settings at a FSB of 190 will provide the same level of performance as the least aggressive settings at a FSB of 200.

TRAS should be TRCD+CAS latency + 2 cycles. This is why TRAS=6 performs better in the above comparison.. Basically smaller isn't always better.

*www.deep-powder.net/OC_Guide/Mem_Mobo_CPU_Overclocking_Guide.htm
 

AlienTech

In the zone
According to this, the default timings and speeds etc only matter for the specified numbers. IE for regular users! Not power users and over clockers.

*www.lostcircuits.com/memory/ddr400/2544275.gif

*www.lostcircuits.com/memory/ddr400/sisoft3.gif

As you can see.... The slowest memory had the highest bandwidth when over clocked. And DDR266-PC2100 performed 20-30% better than DDR400-PC3200 or even DDR466-PC3500. At 300 MHz FSB with the memory at the 320 MHz setting for a total of DDR480 it gets 6422MB/S which is 50% faster than even Dual channel setup.

*www.lostcircuits.com/memory/ddr400/10.shtml

Oh yea its running @ 2.5:4:4:8

Of course running it at the default standard speeds, these memory would be 10-20% slower than the high performance ones.

So over clockers buying those high performance high cost ram dont really have the fastest ram or the widest bandwidth :)
 

sunmysore

Journeyman
Hmmm....saw some gr8 ram last week...

tehre was this 512MB sticks of Winbond UTT CH-5.....and there was Winbon UTT BH-5 256MB sticks...

i got a couple of the BH-5 sticks...they do 260MHz 2-2-2-5 at 3.3V , memtest stable on the DFI nf4 ultra...wonderful....

would like to get the CH-5 too, but no cash :(
 
Status
Not open for further replies.
Top Bottom