CPU-Z question....

[RyanGreener]

What does it mean when CPUID/CPU-Z states that the FSB:Memory ratio is CPU/13? For the record, my multiplier is 13 instead of 14, and the FSB has been slightly overclocked. Should I just assume that the DRAM Frequency is the same as FSB no matter what?

 

[heyheybooboo]

Click the memory tab.

Under the memory tab you will find your DRAM Frequency.

AMD memory is 'double-pumped'. So your memory speed will be the DRAM Frequency x 2.

OR

You may take the Bus Speed from the CPU tab and multiply by your memory ratio as set in the BIOS.




--

 

[jvroig]

What tab are you looking it? Are you referring to FSB: DRAM under the memory tab? Can you post a screenshot of it?

Far as I can remember, CPU-Z has always shown the FSB:Memory to be a ratio, like "1:1", "1:1.33", "1:1.66", "1:2", or as in the sample screenshot in the CPU-Z site, "4:16". It's not the same as the BIOS setting (I remember being confused when I first saw it), but I don't remember ever seeing it as "CPU/13"

The DRAM frequency is affected by the FSB and the DRAM mul or FSB: DRAM ratio (as with other settings, it gets called differently in different BIOSes). Depending on what the FSB: DRAM is (for example, 1:2), the DRAM frequency changes despite the FSB being constant. For example, for DDR2 RAM, if FSB = 200, and FSB: DRAM is 1:1.66, then you get a DRAM freq of 667 MHz (200 x 1.666666 x 2). If you change the ratio to 1:2, then the DRAM freq would be 800 MHz (200 x 2 x 2).

EDIT: Smilies for ": D" are annoying when quick replying, removed.

 

[RyanGreener]

Sorry for being vague. It is an AMD processor and DDR2 Memory, and it is under the memory tab. A friend told me it should read 1:1. 9:10, or some other actual # rating. Mine says CPU/13, but if you do the calculations, CPU/13 actually ends up being the DRAM frequency so I am guessing the ratio is basically 1:1 and that the BIOS is somehow getting the magical #. My BIOS can't lower the memory ratio to "3.33" as suggested in the other topic, but what I did was I went in BIOS, and picked an option to LIMIT the memory ratio to 400 mhz so it won't go past it, which it normally did when I set it to auto.

 

[jvroig]

If you limit it to 400, that's 1:1 all right.

Just curious, what are the settings for your memory ratio? The options displayed are different depending on the BIOS even though they actually mean the same thing, so "3.33" is actually the same as "x1.66". I suppose it is also possible that your BIOS has options in memory ratio in the same way that a lot of BIOSes have options for HT Link multiplier - by showing the supposed frequency at stock ("1000MHz" instead of "x5", for example), which is why you see "400MHz" instead of "1:1" or "2".

 

[RyanGreener]

If you limit it to 400, that's 1:1 all right.

Just curious, what are the settings for your memory ratio? The options displayed are different depending on the BIOS even though they actually mean the same thing, so "3.33" is actually the same as "x1.66". I suppose it is also possible that your BIOS has options in memory ratio in the same way that a lot of BIOSes have options for HT Link multiplier - by showing the supposed frequency at stock ("1000MHz" instead of "x5", for example), which is why you see "400MHz" instead of "1:1" or "2".

I am not sure how to edit the memory ratio, but the closest option I had to it was picking Auto or 4 different values. The lowest one was 400 MHZ (which I was told in this case, is considered a multiplier of x4, while 333 MHz would be 3.3, right?), and that x2 = 800 MHZ. There were 3 modes for it. Auto allowed the BIOS to pick the value, manual tried to lock it as that value, and limit made sure it never go past that value. I tested things, and when set to auto on stock multiplier and raised FSB, my DRAM Frequency in CPU-Z would be over 430 MHZ, but all things kept the same, when I used "limit" my DRAM Frequency was lowered. If this helps at all, I lowered my HT Link Multiplier to x3 instead of lowering to just x4, as I read somewhere that some motherboards like x3 better for stability.

 

[jvroig]

If 400MHz is the lowest, then that would be:
- "1:1" (in BIOSes where the multis are shown as ratios: "1:1", "1:1.33", "1:1.66", "1:2")
-"x1" (in BIOSes where the multis are "x1", "x1.33", "x1.66" and "x2")
-"x2" (in BIOSes where the multis are "x2", "x2.66", "x3.33" and "x4")

I've encountered all three cases above from the different boards I've had. This is the first time, however, that I've seen memory ratio / DRAM multipliers expressed in MHz like HT Link Freq, so I guess this means your options are: 400MHz, 533MHz, 667MHz, and 800MHz. Is that an accurate guess?

 

[RyanGreener]

so I guess this means your options are: 400MHz, 533MHz, 667MHz, and 800MHz. Is that an accurate guess?

Correct. If it helps, it's a Foxconn 770 ATX mobo

 

[jvroig]

Well, then, that clears it up. Whenever someone says "1:1.33" (the most common way to specify the DRAM ratio) or another setting, you can just convert like this:

1:1 = 400 MHz
1:1.33 = 533 MHz
1:1.66 = 667 MHz
1:2 = 800 MHz

Stock DDR2 runs at 1:1.66 (rated at 667 MHz in labels) or older ones at 1:1.33 (533 MHz), so if you overclock, you can just set it down one notch. Unless your DDR2 is one of the earlier DDR2 sticks released, that's almost guaranteed to be at least 667MHz, so you can comfortably drop down your ratio to 1:1.33 - even if your HT ref clock / FSB is 250, you are merely back at stock speed for your ram (250 * 2 * 1.33 = 665MHz).

 

[RyanGreener]

Well, then, that clears it up. Whenever someone says "1:1.33" (the most common way to specify the DRAM ratio) or another setting, you can just convert like this:

1:1 = 400 MHz
1:1.33 = 533 MHz
1:1.66 = 667 MHz
1:2 = 800 MHz

Stock DDR2 runs at 1:1.66 (rated at 667 MHz in labels) or older ones at 1:1.33 (533 MHz), so if you overclock, you can just set it down one notch. Unless your DDR2 is one of the earlier DDR2 sticks released, that's almost guaranteed to be at least 667MHz, so you can comfortably drop down your ratio to 1:1.33 - even if your HT ref clock / FSB is 250, you are merely back at stock speed for your ram (250 * 2 * 1.33 = 665MHz).

Just trying to clarify, are you saying that since my DDR2 is rated at 800 MHz on the label, would you say in the BIOS that would equate to the actual 800 MHz option? I thought that since it was double data rate, it would be the 400 MHz x 2. Cause in the other topic when I tried to overclock, it was suggested to try and get a 1:1 ratio by lowering the memory multiplier from "4" to "3.33"

 

[jvroig]

Just trying to clarify, are you saying that since my DDR2 is rated at 800 MHz on the label, would you say in the BIOS that would equate to the actual 800 MHz option?

In your BIOS, yes. The confusion is because different BIOSes show different 'labels' for the same settings. For example, your "400MHz" is the same as "1:1" in my gigabyte board, and the same as "x1" in my MSI board.

Evidently, your foxcon board is saving you the trouble of having to compute things in your head (FSB * FSB: DRAM ratio * 2), so instead it shows you what the actual DRAM freq will be, assuming that the FSB / HT ref clock is at stock. This is why I keep on referencing HT Link Frequency, because its multipliers (x1 - x10) are often expressed in MHz as well. The downside is when the FSB / HT ref clock is not at stock (i.e., you are overclocking or underclocking), their labels become misleading, because in reality they are not expressing MHz but multipliers.

EDIT:
Example to illustrate: If you choose 400MHz, but your HT ref clock / FSB is at 250, your RAM won't actually be running at 400 MHz (unless you choose the "LIMIT" option, something I have not seen before), you will be running at 500 MHz. In this scenario the label therefore becomes misleading, because it seems you chose 400MHz, but since it is actually a multiplier, you won't get exactly 400 MHz unless your FSB remains at 200.

 

[RyanGreener]

Forgot to mention, here's a picture of what I am talking about.

This is my exact mobo + mobo screen, but it happened to be on a review site. 🙂

 

[RyanGreener]

EDIT:
Example to illustrate: If you choose 400MHz, but your HT ref clock / FSB is at 250, your RAM won't actually be running at 400 MHz (unless you choose the "LIMIT" option, something I have not seen before), you will be running at 500 MHz. In this scenario the label therefore becomes misleading, because it seems you chose 400MHz, but since it is actually a multiplier, you won't get exactly 400 MHz unless your FSB remains at 200.

Ohh, so does this mean I should choose the "manual" option to make sure my memory is faster? As long as I don't run it over 800 MHz I will be fine right?

 

[jvroig]

This is my exact mobo + mobo screen, but it happened to be on a review site.

Yep, looks like multipliers to me. 400 is the lowest, so that's definitely 1:1. Follow the conversion I mentioned in post #9 and you'll be fine.

So, unless you actually want to run your RAM way below its rated frequency, choose 1:1.66 or 1:1.33 (667MHz or 533MHz) while overclocking with the FSB up to 240-250 and you don't want to overclock your RAM much or at all.

Ohh, so does this mean I should choose the "manual" option to make sure my memory is faster? As long as I don't run it over 800 MHz I will be fine right?

Yes. Right, perfectly fine.

Just for reference, I've got 4 sticks of DDR2 rated at 667. They all go as far as 920+MHz safely.

 

[RyanGreener]

Yep, looks like multipliers to me. 400 is the lowest, so that's definitely 1:1. Follow the conversion I mentioned in post #9 and you'll be fine.

So, unless you actually want to run your RAM way below its rated frequency, choose 1:1.66 or 1:1.33 (667MHz or 533MHz) while overclocking with the FSB up to 240-250 and you don't want to overclock your RAM much or at all.


Yes. Right, perfectly fine.

Good stuff to know. I'm actually running it at:

FSB: 240 MHz
CPU Multiplier: x13
HT Link Multiplier: x3
CPU Voltage: +50 mV
RAM Limit 400 MHz

Stable for 6 hours OCCT and 30 minutes OCCT Linpack. I doubt I will see any performance gains from running the RAM higher than it is now, but at least I can feel comfortable about it. It runs at about 61C right now at full load, but the crit temp is 70 for this. I recently ordered a 70 dollar cooler though. Spire Eclipse II 🙂

According to calculations, 240 MHz x 1.66 (from the 667 MHz multiplier) = 398, multiplied by 2 gets me to about exactly 800 MHz. Good stuff.

 

[jvroig]

Nice, that's a 20 percent overclock. If you remove the limit and go manual and choose "1:1.66"/"667MHz", your RAM speed will double, since as I understand it, you are forcibly limited now to absolute of 400MHz, so going manual and 1:1.66 will mean reaching 800MHz again.

61C is fine for an Athlon 64 X2 (if I remember your proc right), especially if that is the Linpack temp already. In real life probably wouldn't even break 56C.

If you ever want to test your RAM (maybe if you try to OC it after you are stable with everything else), MemtestHCI is great (within Windows), and Memtest86+ for a bootable solution before Windows loads.

 

[RyanGreener]

Nice, that's a 20 percent overclock. If you remove the limit and go manual and choose "1:1.66"/"667MHz", your RAM speed will double, since as I understand it, you are forcibly limited now to absolute of 400MHz, so going manual and 1:1.66 will mean reaching 800MHz again.

61C is fine for an Athlon 64 X2 (if I remember your proc right), especially if that is the Linpack temp already. In real life probably wouldn't even break 56C.

Yes, I changed the LIMIT 400 MHz to MANUAL 667 MHz and it runs at 390 DRAM FREQ now, which is about 800 MHz.

I wanted to buy the cooler so I can overclock it more, haha. The car parts can wait for a bit, it was just 70 bucks anyway. I hope that my motherboard can handle it though. My board is rated at 95W, and stock TDP for my CPU is 89W, but I've seen people say things like "I've put 125W CPUs on this" and "Foxconn stated it was good for 125W". Not sure what to think of that...especially cause I don't know what my TDP is now that I've OC'd.

2.8 GHZ Stock ---> 3.112 GHZ OC
Stock Voltage 1.35V ---> 1.4V OC

EDIT: Yes, I have burned a CD for memtest already and I've been using it everytime I tried OCing this thing so far. It's always good 😀

 

[jvroig]

Not sure what to think of that...especially cause I don't know what my TDP is now that I've OC'd

TDP always shoots up anyway when overclocking is in the picture, so don't worry about it.

You'll know if your board can take it through stress-testing, which you've already done. If the PC just reboots (and no BSOD) while heavily loaded in a stress-test, and giving even more vcore doesn't seem to correct the problem, it's probably the board not able to keep up, and then you'd recognize your limit.

So until you start failing stress tests, just don't worry about it.

Of course, not to say your board will live long and prosper or anything. Can't predict that. So far, though, I've got two machines both overclocked (one at home, one at work, but both are owned personally by me, not by the company) to as high as possible, both haven't bombed on me yet.

 

[RyanGreener]

TDP always shoots up anyway when overclocking is in the picture, so don't worry about it.

You'll know if your board can take it through stress-testing, which you've already done. If the PC just reboots (and no BSOD) while heavily loaded in a stress-test, and giving even more vcore doesn't seem to correct the problem, it's probably the board not able to keep up, and then you'd recognize your limit.

So until you start failing stress tests, just don't worry about it.

Of course, not to say your board will live long and prosper or anything. Can't predict that. So far, though, I've got two machines both overclocked (one at home, one at work, but both are owned personally by me, not by the company) to as high as possible, both haven't bombed on me yet.

Good to know. If it lasts over 2-3 years I am good enough, cause I need to go modern and get DDR3 memory and a modern CPU anyway. I'm going to aim for a stable 3.3 or 3.4 GHZ on this thing for now.

 

[tweakboy]

That is what you get when you get a cheap PCB mobo like Foxconn.

Foxconn or Acer are the top two worst companies to buy from. 🙁 Bad researching or just wanted to go cheap when a bit more would have not gotten you into this situation in the first. the BIOS is limited to like 3 options LOL same as Acer, actually my cousins Acer from fry has literally no BIOS options,,, sad. Thank you and GB

 

[jvroig]

That is what you get when you get a cheap PCB mobo like Foxconn.

Foxconn or Acer are the top two worst companies to buy from. Bad researching or just wanted to go cheap when a bit more would have not gotten you into this situation in the first.. Thank you and GB

Cool story, bro :thumbsup:

 

[heyheybooboo]

....

According to calculations, 240 MHz x 1.66 (from the 667 MHz multiplier) = 398, multiplied by 2 gets me to about exactly 800 MHz. Good stuff.

The fine folks at Foxconn did the math for you (as you have discovered). The '667MHz' setting is 333MHz x 2 (the 'double-pump'). See how easy the math gets once you figure it out? 3.33 x 240MHz! The 533MHz setting will be 2.66 x 'the clock'.

The issue now in front of you is the dreaded AMD Volt Wall. You will reach a point where you really have to crank the vcore for a marginal return in clock speed. If you can go 13.5 x 240MHz @ 1.4v you should be very happy.

I suspect you may need 1.425v to get there --- getting to 3.3-3.4GHz may well require 1.45-1.5v for 14x240MHz.



(You may want to 'Iggy' tweakboy 🙂 )




--

 

[VirtualLarry]

AMD cpus use a memory divider, and it is linked to the overall clock speed of the CPU, not the "FSB" times some multi, like the Intel 775 CPUs are.

So the overall memory divider is shown as "CPU/*divisor*" in CPU-Z.

 

[RyanGreener]

That is what you get when you get a cheap PCB mobo like Foxconn.

Foxconn or Acer are the top two worst companies to buy from. 🙁 Bad researching or just wanted to go cheap when a bit more would have not gotten you into this situation in the first. the BIOS is limited to like 3 options LOL same as Acer, actually my cousins Acer from fry has literally no BIOS options,,, sad. Thank you and GB

The computer came to me like this, but thanks for posting your opinion.

 

[jvroig]

The computer came to me like this, but thanks for posting your opinion.

It's tweakboy. You just have to either "iggy" him as heyheybooboo mentioned, or just enjoy and get a good chuckle from his posts. Last thing you should do is take it personally (not saying you did there, just giving out some unsolicited advice, seeing as to how you might yet be unacquainted with the tweak-man).