RAM/FSB/RATIO

hello oc'lers
just a simple question i often read that most people set their ram ration to 4:5 meaning using 333instead400ddr etc.
So my question you slow down your ram to get more cpu speed???
I dont understand that if you slow down one componed how can the whole system be faster??

Excellent treatise on FSB and DDR clocks!
Quote
Will the NVidia GPU work faster if I have a faster CPU?
Sorry, but I meant to imply the answer. The long of it is despite offloading most graphic operations to the GPU, a significnt part of display drivers are still executed by the CPU, so YES - by increasing FSB, graphic operations should also run faster :D
Having said that, please note that you won't be able to have a 10% increase in FSB result in a corresponding 10% in application performance OR benchmark results because of inter-dependencies.
Check out this review on a comparison of the same video card on 2 systems with diff proc speed (and architecture)
VGA Charts, Part II: Mainstream Systems

Similar Messages

MOVED: ram:fsb ratio

This topic has been moved to Overclockers & Modding Corner.
ram:fsb ratio

What kind of ram do you have? You'll need to raise vcore soon, and probably ram voltage as well depending on your ram. Check the ram voltage perimeters too so you don't burn it when overclocking. Also in bios, make sure spread spectrum is off and agp frequency is set to 66. Oh yeah, don't ever trust core center readings. Those readings are always being misreported. I only trust cpu-z and everest for readings.

975 Platinum Powerup BIOS & Ram FSB

i have the 975X Powerup edition
dual core 805
OCZ 5400 Gold 667 RAM
my ram only comes up as 533MHz but is has occasionally run at 667MHz. when i go into the BIOS and look at RAM FSB multiplier i can not change it of AUTO as it is read only.
any help would be appreciated.

You should have a read of this review, to learn more about your processor but the ratio will not go higher then 1:2 so you may have to push up your FSB to get more out of your memory but I am not 100% certain on this. Maybe someone who is already running with your proc will post for you.
http://www.neoseeker.com/Articles/Hardware/Reviews/intel805d/
Gaucho

DRAM:FSB Ratio Question

I'm new to OCing & have put a mild 3GHz OC on my CPU. Everything is stable, the only thing I'm concerned about is my DRAM:FSB ratio. It is 6:5. I thought 1:1 is ideal & have been trying to search all morning on the means to achieve it before asking the question here. Here's what my Cell Bios look like.
D.O.T.= Disabled
Intel EIST= Disabled
System Clock Mode = Linked
FSB Clock (MHz) = 1333
Adjusted Dram Freq = 800 (greyed out)
Adjusted CPU Freq = 9
Adjusted DRAM Config = 4-4-4-15, 22trc, 2T
Adjusted PCI-E Freq = 100
CPU Voltage = 0
Memory Voltage = 2.1
UTT FSB Voltage = 1.2
NB Voltage 1.2
SB Core Power = 1.5
Spread Spectrum = Disabled
It is my understanding that I don't need to up my voltages for a 3GHz OC. I got my memory timings stable after I discovered I have a bad HD & replaced them. What do I need to do to get to 1:1 or should I even be concerned about it? Everthing is stable at this point & I'll stick with 3GHz until I can learn more.

I also noticed that Vantage also didn't get my FSB correct, I am running 417 but it showed 333. It also showed wrong clocks for my graphics card OC.
http://valid.x86-secret.com/show_oc.php?id=380800
http://service.futuremark.com/resultAnalyzer.action?resultId=94260&resultType=18
I am using the latest patch from Nov. 2007 and the last time I checked there were no new patches yet.

HELP: X48 Platinum, lower FSB ratio to 1.6, no boot

Hi, everyone. I'm new here, so I hope you'll forgive me if I ask a dumb question.
I'm having a problem setting up my system to over-clock my processor, and I'm getting caught in a very early step where I don't expect a problem, and I'm hoping maybe someone can give me some suggestions.
Here's my setup:
- X48 Platinum
- Intel Q9450 (45nm, 2.66GHz, 4x333MHz FSB)
- 4x 2GB Crucial DDR3, 1333MHz
I started by setting everything to defaults. CPU multiplier is 8x, FSB is 333, memory/FSB ratio is 2.0, memory is using SPD, all voltages are on Auto. (Except the memory voltage, which I had to bump to 1.58 to make it work with all four slots populated). In this state, everything works perfectly. I run stress tests, and everything is peachy.
Next thing I did was lower the memory/FSB ratio to 1.6, which would run the memories at 1066MHz. When I do that, the system won't boot. The LEDs on the motherboard say "ICH", which means that it's somehow getting stuck when initializing the southbridge.
Can anyone give me some insight into what is going on here and how I might fix this problem? How could UNDERclocking the memory cause the system to not boot? And how could I work around it?
I also tried manually setting the memory timings to what I know to be in the SPD, but that didn't help. Another thing I did was raise the FSB speed to 417MHz so that the memory would be back up at 1334MHz and lower the CPU multiplier so it would be below 2.66GHz. That didn't help either, but it's not where I want to start since I don't yet know the correct terminator and threshold voltages. I'm not sure what else to do here.
Thanks.

Quote from: RemusM on 09-April-09, 03:17:04
Let's forget about wikipedia and books for newbies.
A DRAM is organized as a matrix (with rows and columns)
tRAS is the time interval between the row accesses.
This signal is also used to refresh the memory cells (the capacitors) on the rows.
High speed + tight timings = incomplete refresh.
In other words, corrupted data.
I'm not disagreeing with you. Among other things, I'm trying to find some other reason to account for the memory having been adequate time, despite the setting. Keep in mind that this is FOUR memory modules that are working at this speed. One explanation is that the BIOS is simply lying about this. That is, I can set the number to 9, but it's not really getting set to 9 in the hardware.
One way to test this is to run a performance test at 7-7-7-20, 7-7-7-16, and 7-7-7-9 to see if it makes any measurable difference. If it doesn't, then there's no reason for me to use the lower number, because there's a risk that whatever magic is saving it's ass right now isn't always going to be true, such as when both heavy CPU activity and DMA are going on at the same time.
Quote
At 1066MHz and 1.58V, it's impossible to get stability if tRAS < 16.
So please, if you're looking for help here, post a screenshot of your SPD settings (use CPU-Z).
You'll see the real timings of your DDR3 modules (not that 7-6-6-9 aberration).
At the moment, I'm not using 7-6-6-9 but 7-7-7-20 as you suggested. So regarding the CPU overclocking help, this is irrelevant. While I am working on overclocking the CPU, I won't be using the "aberrant" timings.
On the other hand, the fact that it ran for 4 days straight error-free at 7-6-6-9 is interesting and may bear some investigation.
BTW, I'm not running Windows. I'm running Linux. I want to overclock, because this is a compute server, and I want my neural nets, genetic algorithms, and Verilog simulations to go faster. If you'd like to see a screen shot of some tool, is there a Linux equivalent to CPU-Z? I'm not interested in spending money on a Vista license just so I can run this program. I do have a valid (and currently unused) license for Windows XP Pro (SP2), but I have a feeling that it won't fully support this board without extensive wranglings with trying to get drivers installed early in the install process. Suggestions?
Did you mean to ask for SPD numbers, or the numbers currently set? As for SPD, I looked up the micron spec on the chips on the memory module and found out that at 1333MHz, it's 9-9-9-24, and I also know the rest of the numbers. I'm not at home right now, but let's see what I can remember. tRFC=74 (but I think the SPD has it set to 60). tWR=10, tWTR=5, tRRD=5... I'm probably misremembering some of those. I'll report later.

845 Ultra ARU CPU FSB Ratios?

The bios provides DRAM Frequencies of 200, 266 and Auto. Given a FSB of 100, that means the ratio of CPU:FSB is 1:1 and 3:4. (What is 'Auto')
If I run the FSB at 133, are these ratios preserved, or does some other ratio come into effect. If I choose FSB of 133 and DRAM Frequency of 266, will I be running at 354 DDR? If so, do you think a stick of Corsair PC2700 (333 DDR) will O/C to that level?

Quote
Originally posted by jdurg
If I recall correctly, once you reach a front-side-bus of 123 MHz, the ratio sticks at 1:1. So at a fsb higher than 123, the memory ratio will ALWAYS be 1:1 no matter what you set it at. X( You are correct on your ratio assumptions, but at 123 MHz the memory ratios become useless. The Auto option is as it suggests. The BIOS will automatically set all the RAM timings per what the chips are rated at. So if you have the memory set to Auto, you won't be able to change the CAS timings and the other various memory options.
The lack of memory ratios on this particular board is what really hurts it. I've got my 1.8A P4 overclocked to 2.52 GHz on a 140 MHz fsb. However, the CPU is being choked to death by a memory bandwidth of only 2.0 GB/s. If there were more memory ratios than the one 1:1 ratio that MSI gives us, I'm sure I could improve my system's performance quite a bit. The other problem with the MSI board, that affects me at least, is that the temperature sensor seems to be out of whack. PC Alert III and MBM5 say that my CPU is at 67-68 degrees Celsius under a full load. With the case open and my hand right on the heatsink during that full load, I can tell you that the reported temperature is at least ten degrees off. If it were really 68C, I would not be able to keep my hand on it without it feeling really warm.
So those are the only two things about the 845 Ultra-ARU that make me really wish I had gotten a different motherboard. :(
Hi jdurg.
I just found a post on Usenet that was very interesting. The poster has an 845 Ultra ARU. Here's the quote:
All this time I used fuzzylogic 4 to overclock my 1.6a to 2.1 @ 133. now I
actually went into BIOS and adjusted my memory settings. This is what I did:
Changed....
DDR Frequency: from 266 to AUTO
Configure DRAM Timing by: from MANUAL to SPD
What I noticed was the CAS# LATENCY changed from 2.5 to 2 (I didn't adjust)
Now I use a program called CPU-Z to get information on the CPU, MB, and MEM.
speeds. Before the changes on the motherboard/CPU speed was normal like:
Before: (with out bios changes)
CPU Frequency: 2119.1 MHz
Clock Multiplier: x 16.0
FSB Frequency: 132.4 MHz
MEM Frequency: 351.4 MHz
before I had problems of computer freezing after a few hours.
Now: (after bios changes)
CPU Frequency: 2119.1 MHz
Clock Multiplier: x 16.0
FSB Frequency: 132.4 MHz
MEM Frequency: 264.9 MHz
also CAS# L: 2clocks, RAS# to CAS# Delay: 2clocks, RAS# Precharge: 2clocks
and Cycle time: 5clocks.
now my main question is how come the MEM Freq. has changed/decreased?
and my system is very stable now (no crashes). is this normal? I have a
no-name, cheap(only paid $60 can.) is this normal for this mem chips?
There was no reply to the message, but it looks like he was getting a 3:4 memory speed ratio with the FSB at 133. This is good! He had DRAM Frequency set to 266 and memory timings set to Manual. Using AUTO and SPD brought his memory back to a 1:1 ratio. My board won't be in until the end of the week... is there anyway you could verify this on your board?

Problem with K7N2 delta :booting issues

my k7n2 wont boot after being unplugged from power unless i reset the FSB jumpers to 100mhz mode. Also, it wont boot when I try to set the ram-FSB ratio different. It will not boot and I have to clear the CMOS to get it to work again. Please help

Quote
Originally posted by bdjohnson
my k7n2 wont boot after being unplugged from power unless i reset the FSB jumpers to 100mhz mode. Also, it wont boot when I try to set the ram-FSB ratio different. It will not boot and I have to clear the CMOS to get it to work again. Please help
How about some info regarding what you are using in the system? We don't have the ability to peer into your office/home to see what's in your system...
If you read the sticky posts at the top of the forum first you may find that you might answer your question first...alternatively do a search regarding your problem and you may find posts that will help you to find answers as well...
Bonz

Replaced K8N Diamond Plus doesn't overclock!!!

Alright I'm bummed! The board worked like a charm and suddenly died last weekend. Got a replacement board under extended warranty and now it doesn't oc anymore. In Bios 1.2 (2006 Jun 6) it shows FSB of 250 but once I got to the Bios boot up screen, I'm seeing 2.2Ghz (200 x 11) again for my A64x2 4200+, what have I done??? I also ran the latest CPU-Z and confirmed that my FSB is only at 200! Should I flash to newer BIOS?

Quote from: alecela on 25-September-08, 01:03:04
Thanks again matey. I've always been under the impression that when they say the RAM/FSB ratio they were referring to the ratio between the RAM speed & FSB speed. Never knew that one need to go through a convoluted calculation w/ rounding up like that! I guess you learn something new everyday!
"Never knew that one need to go through a convoluted calculation w/ rounding up like that! I guess you learn something new everyday! "
The FSB is the wrong term used,{your board don't have FSB} Its called CPU reference clock.
"I've always been under the impression that when they say the RAM/FSB ratio they were referring to the ratio between the RAM speed & FSB speed."
Yes, that's correct. But memory freq. also depend of CPU overall freq., CPU MP used. Also memory divisor can be solid number only.
So you have to assume all factors to gain the memory frequency.

P35 Neo Combo DDR3 1066MHz

Hi Guys,
I would like to upgrade (increase) memory size on the following system:
MSI P35 Neo Combo (bios ver. 1.3)
CPU Intel Core 2 Duo E6750
VGA Radeon HD 5770 1GHz
current memory 2x1 GB DDR2 800 Mhz
It is a few years old system and I wanted to put extra memory there. The mobo only supports up to 4GB (DDR2 or DDR3). As the DDR3 modules are cheaper today than DDR2, I bought 2x2GB DDR3 1066MHz (PC3-8500 CL7 Kingston) that should be supported by this mobo. But when I place the new moduls into slots the system does not boot . Of course, I took out the DDR2 modules before applying the new ones.
Do you have any clues where could be a problem? Manual BIOS settings of some parameters? Or to update BIOS to the newest version 1.7?
Thanks a lot in advance for any hints...

Quote from: beethoven on 21-January-13, 20:18:18
Voltage is set to auto - I will try to set it manually on 1.55 or 1.60V and will se if it helps. Just a short question - if deafult setting for RAM module is 1.5V, can voltage of let's say 1.60V somehow harm it?
Regarding the timings: at the moment the timings are set automatically by SPD. If I look at the specification of these modules (http://www.micron.com/parts/modules/ddr3-sdram/mt8jtf12864az-1g6) they have native CL10 but it is probably for default speed 1600MHz. Is CL7 for speed 1066MHz "overclocking" for this module?
Anything below 1.65V is ok for a DDR3 module.
Also, it's highly recommended to use 1.55-1.60V (instead of 1.50V) on older mainboards (and not only).
Now talking about timings.
7-7-7-20 are the default timings for DDR3-1066
9-9-9-24 are the default timings for DDR3-1333
You cannot use the SPD profiles of a DDR3-1600 module, if you want to make it run at 1066MHz.
So you need to manually change the RAM/FSB ratio, timings and voltage.

Ram ratio

first of all how do you change your ram ratio on msi 875p
and am i right in thinking that 1:1 is best for performance
my specs:
msi 875p neo fis2r
p4 2.6(533fsb)(changing to p4 3ghz 800fsb)
pc2700(ddr333)dane elec(changing to k'ston hyper x pc3700 )
geforcefx 5900
audigy 2
6.1 inspire spks
antec true blue 480x psu

If you have a P4C (800FSB) CPU, these are your available FSB:RAM clock ratios:
CPU=200 DRAM=532 gives FSB:RAM=3:4
CPU=200 DRAM=500 gives FSB:RAM=4:5
CPU=200 DRAM=400 gives FSB:RAM=1:1 -> AUTO default
CPU=200 DRAM=333 gives FSB:RAM=5:4 (865/875DRAM=320 MHz due to )
CPU=200 DRAM=266 gives FSB:RAM=3:2
As you change "Adjust CPU Bus Clock" from the 200 MHz default, your DRAM frequency also changes based on the corresponding FSB:RAM ratio.
If you have a P4B (533FSB) CPU, these are your available FSB:RAM clock ratios:
CPU=133 DRAM=354 gives FSB:RAM=3:4
CPU=133 DRAM=333 gives FSB:RAM=4:5 -> AUTO default
CPU=133 DRAM=266 gives FSB:RAM=1:1
If you have a P4A (400FSB) CPU, these are your available FSB:RAM clock ratios:
CPU=100 DRAM=266 gives FSB:RAM=3:4 -> AUTO default
BTW - on my system with a P4 1.8A , I have the ff. options available with BIOS 1.6 up to 1.8 beta:
DRAM Frequency = 266, 333, Auto, 354
But with DDR400 installed , I can't get it to boot with DRAM=333 or 354 settings.

2100 ram vs. 2700 ram (or higher) - FSB speeds matching with CPU

Question regarding 2100 RAM vs. 2700 RAM or even higher...
My system specs are below. Would replacing my 2100 RAM with 2700 RAM make any difference in system performance? I was under the impression that your CPU FSB basically worked in coordination with your RAMs.
So, say my CPU is a 266fsb (set at 133 in the bios), and my 2100 ram is also 266fsb...
If i upgraded to 2700 ram, wouldn't my ram still run at 266fsb because the CPU is still running at that speed?
Hopefully my question is clear enough. I see people recommending upgrading to 2700 ram or even 3200 ram, but I didn't think it could run any faster unless your CPU FSB was matched up with the RAMs FSB.

If you buy anything buy PC3200 (DDR400) since PC2700 isn't any cheaper.
But you are correct, you will see little to no differance in preformance since the CPU's FSB is already matched.
The board can run the FSB at 266 and the RAM at 400, but it gives little in preformance terms for the above reason.
There is a slight preformance agvantage since the extra bandwidth might be usefull for DMA operations (HDD, AGP writes etc..) but not very noticable in a PC.

Lenovo 3000 N200 (0769) 4gb of RAM only 3gb recognized

I know I know it,s "normal"!
I have installed 4GB of RAM but I'm running Windows XP 32-bit SP2
I,ve read somewhere that to be able to upgrade from XP 32-bit to Vista 64-bit, we only needed to make sure that :
1. you need to HAVE a 64 bit processor.
2. the motherboard and bios MUST be 64 bit enabled.
3. the chipset MUST be 64 bit compatible
So I've been using PC Wizard to check my computer's information and here's what I see :
Product :    IEL10
Version :    REFERENCE
Serial Number :    -------------
Support MP :    Yes, 2 CPU(s)
Version MPS :    1.4
SouthBridge :    82801HEM (ICH8M-E) LPC Interface Controller
NorthBridge Information :
Architecture :    Direct Media Interface (DMI)
Manufacturer :    Intel (Legend Ltd)
Codename :    Crestline
Revision :    C0
Bus Speed :    133 MHz
FSB Frequency :    532.1 MHz (QDR)
Bios information :
Version :    68ET37WW
Date :    06/11/2008 (mm/dd/yyyy)
Address :    0x0 on 1024 KB
DMI Version :    2.4
Frequency :    266 MHz
DRAM/FSB Ratio :    2/1
Supported Channels :    Dual (128-bit)
Activated Channels :    Dual
ECC Diagnostic :    Non
CAS Latency (tCL) :    4 clocks
RAS to CAS (tRCD) :    4 clocks
RAS Precharge (tRP) :    4 clocks
Cycle Time (tRAS) :    12 clocks
Shared Memory (video) :    Yes
<
Internal Specification :    Intel(R) Pentium(R) Dual CPU T2370 @ 1.73GHz
Model Number :    T2370
Codename :    Merom
Revision :    M0
Technology :    0.065µ
CPU ID :    6.F.D
CPU IDEx :    6.F.D
Microcode :    MU06FDA3
Mobile :    Yes
Instructions :
IA-64 Technology :    No
Intel64 (EM64T) :    Yes
Can anyone confirm that I really have ALL IT TAKES to move on to Vista 64-bit? Or anything else I should check before upgrading?
Thanks a lot for your help guys!
Kim

Wow, thank you, what an awesome little tool!
So, I found that these 2 RAM products are compatible with my laptop:
Part Number: CT758799
Module Size: 2GB
Package: 200-pin SODIMM
Feature: DDR2 PC2-6400
Specs: DDR2 PC2-6400 • CL=6 • Unbuffered • NON-ECC • DDR2-800 • 1.8V • 256Meg x 64 •
Part Number: CT699699
Module Size: 2GB
Package: 200-pin SODIMM
Feature: DDR2 PC2-5300
Specs: DDR2 PC2-5300 • CL=5 • Unbuffered • NON-ECC • DDR2-667 • 1.8V • 256Meg x 64 •
I then went to a well-known auction site and found RAM cards from the same manufacturer with exactly the same specs as above but with different Part numbers. Does it have to be the exact part number or do I stand a good chance of it working if it has the required spec? I searched for the exact part numbers and yielded 0 results.
Thanks for all your help on this.

How can I overclock my RAM

Hi,
I have the system written in my signature.
My FSB is 398.4 and my Core Speed is at 2191.2
My RAMs are at frequenced at 166Mhz. And they work as DDR 333mhz Dual channel 512x2.
Is there any way I can overclock these RAMs to work at DDR 400?
Thanx in advance.

if you set your dram:fsb ratio to 1:1 it will make the ram frequency the same as the fsb. you will not likely be able to OC your ram in dual channel. i dont know how well the ram will OC either.
good luck

CPU ratio

hi there
I have just bought a new CPU and it only runs at 2080 mhz (20.5 * 166. I have tried to raise the ratio with 0,5 from 12,5 but then it only runs at 833 mhz, when it should run at 2158 mhz. Does anyone have any suggestions, to what I can do to make it run faster. I have tried to overclocked it in many ways, without results. But then it gets unstable, and my com just stops answering.
If anyone has any ideas, please let me know. Here is my com specifications:
k7n2 delta-l mainboard
Silent viking II @ AMD Athlon Thoroughbred XP 2600+ 2.133GHz, bulk Socket A /333
msi geforce4 4600 128 ram
512mb ddr 3200 (samsung) cl 2,5
7 case fans

Quote
Originally posted by backwoodz
Quote
In what bizaro world is 333 faster than 400?
In the bizarre world of NForce and its buggered asynch settings....That is what this converstion was about Loopy....333/333 synch is faster than 333/400 asynch
Sorry, I thought uiq wanted to run his ram/fsb 400/400 to which he was told 333 was faster.

P7N Diamond RAM Problems

Hello,
first of all sorry for my bad english. I have an Acer G7700 Predator after a Board mailfunction i bought a "real" P7N Diamond. After assembly i got some problems. The system bacame instable. I have an qy9650 Extreme with 4 x 2 GB Kingston KHX8500D2t1. When i set all Bios options in cell menue on AUTO the regonize the RAM as 800 MHZ Ram with 400 Mhz DRAM Frequency. This seems to be the right default settings. In the hardware maintaince manual of Acer the FSB is set to 1333 Mhz with a DRAM Frequency of 400 MHZ. With this setting my system becames extreme instable. So i set the DRAM Frquency to 533. The System runs over 2 hours stable with rigth mark memory tester. After that i set the DRAM Frequence to 333 MHZ to get an 1:1 DRAM FSB ratio. Systems runs stable. Now i wonder how i get the RAM work into 400 MHZ Mode ? Mabye i need some instruction to understand the dependency between FSB-DRAM.

Quote
Is it important to have an FSB:DRAM Ratio of 1:1 ?
No, not at all.
Quote
How much difference is between 667 and 800 Mhz ?
DDR2-800 will, of course, be faster. Only a couple of percent, but definately noticeable in benchmarks.
DDR2-800 is usually not a problem. However, the fact that your are using four modules puts a lot of stress on the memory controller and on the memory bus in general. That is why it sometimes takes slight voltage bump to get things stable. As I said earlier, 1.95V should be enough. Perhaps 1.9V already is.

RAM/FSB/RATIO

Similar Messages

Maybe you are looking for