How to overclock this system?

[Dougmeister]

Gigabyte GA-MA78GM-S2H Motherboard
PNY XLR8 2GB (2x1GB) Dual Channel Kit DDR2 1066 MHz PC2-8500
AMD Athlon 64 X2 Dual Core Processor 5000+ 2.60 GHz

RAM description says:

"Runs at 1066 MHz CL5 with 5-5-5-15 timings at 2.2 volts" but I don't know how to change those settings.

I've had the system for about two years and have not done any overclocking yet. Any help you can provide would be appreciated. Thanks.

 

[TankGuys]

Just do a Google search for Athlon X2 overclocking guide. There's tons of them out there, those chips were fun to OC!

This one is decent enough to get you started: http://www.overclock.net/overclock.php?file=articles/overclocking-guide.htm

 

[Dougmeister]

Thanks. Reading your link now, doing some Googling, too.

So I change all of the settings in the BIOS? Just for the CPU or are there settings for the RAM, too?

 

[TankGuys]

Thanks. Reading your link now, doing some Googling, too.

So I change all of the settings in the BIOS? Just for the CPU or are there settings for the RAM, too?

There are settings for RAM too, generally speaking.

 

[ShawnD1]

RAM description says:

"Runs at 1066 MHz CL5 with 5-5-5-15 timings at 2.2 volts" but I don't know how to change those settings.

Changing the RAM speed does almost nothing positive, but it greatly lowers system stability. I strongly recommend you do not overclock your RAM. Try to keep it either at stock speed or below stock speed.

So I change all of the settings in the BIOS? Just for the CPU or are there settings for the RAM, too?

All of the speeds are tied together by a reference clock. In the older computer it's called "front side bus" (FSB). In the newer computers it's called "HT eference clock". The CPU will have its own multiplier of this reference speed. If your CPU is rated for 2600MHz and the HT reference clock is 200, that means the CPU multiplier would be 13. You can't turn the multiplier up, but you can turn it down. Auto is the best multiplier setting for the CPU.
Memory will also have its own multiplier. The memory multiplier is one you'll need to manually set in order to maintain stability.

What you do is actually very simple. Increasing the HT reference clock will make the CPU and RAM faster. At the same time, lower the memory multiplier so the RAM doesn't run beyond its rated speed.

For example, my E6600 has a rated bus speed of 266MHz, and the memory in that computer is rated for 1066. That would make the memory multiplier 4 since 266 * 4 = 1066. To overclock the CPU, I have the bus set to 300MHz. I want to maintain full stability, so I figure out what the multiplier should be to make the memory 1066.
1066 / 300 = 3.55 multiplier, round down to keep the memory below 1066.

We shouldn't give too much information about this at one time. Once you get a basic understanding of this, come back for more details

 

[Martimus]

Changing the RAM speed does almost nothing positive, but it greatly lowers system stability. I strongly recommend you do not overclock your RAM. Try to keep it either at stock speed or below stock speed.


All of the speeds are tied together by a reference clock. In the older computer it's called "front side bus" (FSB). In the newer computers it's called "HT eference clock". The CPU will have its own multiplier of this reference speed. If your CPU is rated for 2600MHz and the HT reference clock is 200, that means the CPU multiplier would be 13. You can't turn the multiplier up, but you can turn it down. Auto is the best multiplier setting for the CPU.
Memory will also have its own multiplier. The memory multiplier is one you'll need to manually set in order to maintain stability.

What you do is actually very simple. Increasing the HT reference clock will make the CPU and RAM faster. At the same time, lower the memory multiplier so the RAM doesn't run beyond its rated speed.

For example, my E6600 has a rated bus speed of 266MHz, and the memory in that computer is rated for 1066. That would make the memory multiplier 4 since 266 * 4 = 1066. To overclock the CPU, I have the bus set to 300MHz. I want to maintain full stability, so I figure out what the multiplier should be to make the memory 1066.
1066 / 300 = 3.55 multiplier, round down to keep the memory below 1066.

We shouldn't give too much information about this at one time. Once you get a basic understanding of this, come back for more details

Also, you want to keep HTT speed under 1000 MHz. Anything over that amount generally makes the chip unstable, and additional Hyper Transport speed does nothing for a single processor desktop.

http://forums.anandtech.com/showthread.php?t=1077
That is the guide I used to overclock my Manchester x2.

 

[Dougmeister]

If your CPU is rated for 2600MHz and the HT reference clock is 200, that means the CPU multiplier would be 13... At the same time, lower the memory multiplier so the RAM doesn't run beyond its rated speed.

Ok, I have an AWARD BIOS. Here is the setting that I think I need:

HT Link Frequency: Auto (current setting), 200, 400, 600, 800 (MHz)

So I think I need to increase the setting from auto (200 probably?) to a higher number, but not sure which one. I need to "lower the memory multiplier so the RAM doesn't run beyond its rated speed." I found a "Memory Clock", but not a "multiplier".

Help?

Other settings I'm not sure about:

VGA Core Control Clock
CPU Clock Ratio
CPU Host Clock Control
PCIE Clock
Set Memory Clock
System Voltage Control
-- DDR2
-- Northbridge
-- CPU

 

[Jovec]

Make sure you understand these basics first.

HT Ref clock x CPU multi = CPU speed
HT Ref clock x HT multi = HT Link frequency
HT Ref clock x Memory multi = Memory speed

(The following may not apply to your CPU, IDK)
HT Ref clock x CPU-NB multi = CPU-NB speed

All of the above speeds are based off of the HT Reference clock. With a default value of 200MHz, we can see that

200MHz x 13 CPU multi = 2600Mhz
200MHz x 10 HT multi = 2000MHz
200MHz x 4 Memory multi = 800MHz (DDR2 800Mhz)
200MHz x 10 CPU-NB multi = 2000MHz


On Black Edition AMD processors, the CPU multi is unlocked. In other words, you can increase it to higher than the default value. If we could increase it to 15, then we get an decent and easy overclock:

200MHz x 15 CPU Multi = 3000Mhz

However, on non-Black Edition CPUs, the maximum CPU multiplier is capped. You cannot raise it beyond what the CPU default is (but you can lower it, more on this later). The only way to overclock non-BE CPUs is to raise the HT Ref clock, as in:

230Mhz x 13 CPU multi = 2990Mhz

But in doing so, since the HT Ref clock is tied to many speeds, we also get:
230MHz x 10 HT multi = 2300MHz
230MHz x 4 Memory multi = 920MHz (DDR2 800Mhz)
230MHz x 10 CPU-NB multi = 2300MHz

Sometimes these results are desirable such as in the case of the CPU-NB, which will show a decent speed improvement when it runs in the 2500-2800 range. Sometimes you won't see much difference, as in the case of the 2300 HT Link of 920 Memory speed over their stock values of 2000 and 800.

In all cases though, we must make sure that whatever speeds we run at are stable and that our temperatures are within spec. Raising the voltage being supplied to these parts is one way to try to make them stable, but you can also damage them by giving them too much voltage. In addition, more voltage means more heat generation, which can be too much for your CPU cooler to effectively remove.

What we can do is lower the multipliers:
230MHz x 9 HT multi = 2070MHz
230MHz x 3.33 Memory multi = 766MHz

You'll notice these are much closer to the stock values and they should be stable without any additional voltages.

Now, the trick is to understand what your BIOS calls these values. Based on this:

HT Link Frequency: Auto (current setting), 200, 400, 600, 800 (MHz)

It seems like your BIOS is already doing the math for you. It's taking the HT Ref clock (200MHz default) and showing you the results of the 1x, 2x, 3x, 4x, etc multipliers. Here's the trick:

Often times what you see are the results of the default HT Reference clock regardless of what you actually set it at. Continuing our example of 230, we should get values of 230, 460, 690, 920, etc. but the bios may not show you that.

You'll have to do the math yourself like so: 1800Mhz / 200 = 9 multi. With a 230MHz Ref clock and a 9 multi we'll get our 2070MHz speed, but we had to choose 1800MHz in the BIOS.

The same thing applies to the Memory clock. It might show you values like 3.33, 4, 5.33. Or it might show you values like 667, 800, 1066, etc. If it's the former, then just multiplier the number by the HT Ref to get the memory speed. If it's the latter, then like in the previous example, assume a default clock of 200 and divide to get the multi. Again, picking 667 MHz (3.33 multi) with our 230 MHz Ref clock will give us a true memory speed of 766.

Some BIOS versions will properly display the results of a changed HT Ref clock, however it should be easy enough to tell if it does because you'll see different values when you change the Ref clock.

 

[Dougmeister]

Increase the HT reference clock to make the CPU and RAM faster.
Decrease the memory multiplier so the RAM doesn't run beyond its rated speed.

I can't find these settings in my BIOS. Can you guys help me out?

Possibly important values:

CPU Clock Ratio: x5, x5.5, ... x13 <--- Important?
CPU Host Clock Control: 200 MHz -> 500 MHz <--- Important?
HT Link Width: auto, 8-bit, or 16-bit
HT Link Frequency: 200, 400, 600, 800 (MHz), 1.0 GHz
Set Memory Clock: DDR 400, DDR 533, DDR 667, DDR 800 <--- Important?
System Voltage Control:
- DDR2: normal, +0.1v, +0.2v, +0.3v
- Northbridge: normal, +0.1v, +0.2v, +0.3v
- CPU: 1.9v, 1.85v, 1.8v, ... 0.8v <--- Important?

CPU-Z gives me:

Bus Speed: 200 MHz
Multiplier: 13
Core Voltage: 1.360v

(BTW, I upgraded my Gigabyte BIOS from F5 to F12a, thinking it might give me more options, etc.)

Edit: After reading the other posts in this thread more closely, I realize that I don't want to change the "HT Frequency" (i.e., "HT Ref clock x HT multi = HT Link frequency"). Therefore, I want to change the "HT Ref Clock", but I don't see that option in the BIOS, unless that is the CPU Clock Ratio...

 

[Dougmeister]

Are these settings in some sort of "hidden" BIOS menu? I've seen reference to it somewhere, but I can't find the link at the moment.

Something about hitting <Ctrl><F1> or <Alt><F1> while in the BIOS, or something like that?

 

[heyheybooboo]

I can't find these settings in my BIOS. Can you guys help me out?

Possibly important values:


CPU-Z gives me:

(BTW, I upgraded my Gigabyte BIOS from F5 to F12a, thinking it might give me more options, etc.)

Edit: After reading the other posts in this thread more closely, I realize that I don't want to change the "HT Frequency" (i.e., "HT Ref clock x HT multi = HT Link frequency"). Therefore, I want to change the "HT Ref Clock", but I don't see that option in the BIOS, unless that is the CPU Clock Ratio...

First: Leave everything on 'Auto' We need to find out if the CPU will unlock. If you win the lottery you will boot that baby into Windows and show us that screenshot of a Quad Phenom

Enter the Advanced Clock Calibration Menu

Set EC Firmware Selection to "Hybrid" -- Set Advanced Clock Calibration to "Auto" Save and Exit BIOS

With that Gigabyte you may Save and Load up to 8 different BIOS profiles using the F11 & F12 keys.




--

 

[Dougmeister]

First: Leave everything on 'Auto' We need to find out if the CPU will unlock. If you win the lottery you will boot that baby into Windows and show us that screenshot of a Quad Phenom

Enter the Advanced Clock Calibration Menu
.
.
.

Set EC Firmware Selection to "Hybrid" -- Set Advanced Clock Calibration to "Auto" Save and Exit BIOS

With that Gigabyte you may Save and Load up to 8 different BIOS profiles using the F11 & F12 keys.
--

I can't find an "Advanced Clock Calibration" menu. Under the "MB Intelligent Tweaker", I have:

- IGX Configuration
- CPU Clock Radio
- CPU Host Clock Control
- HT Link Width
- HT Link Frequency
- Set Memory Clock
- DRAM Configuration
- System Voltage Control

FWIW, the copyright on mine is 1984 - 2010...

Edit: according to the screenshots on this website, that menu option has things like "CPU Clock Ratio", "CPU Northbridge Frequency", and "CPU Host Clock Control". I have those options under "System Voltage Control", if that helps...

 

[heyheybooboo]

Sorry ... Ignore me.

Your motherboard (-S2H) has the sb700 that does not support ACC.




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[Dougmeister]

OK, thanks for trying!

Anyone else? I feel slightly closer, but still missing some key stuff...

 

[Wizlem]

I have the GA-MA78GM-US2H and it sounds like our overclocking options are pretty much the same. The number you need to increase that everyone is calling "HT Reference clock" is called CPU Host Clock Control in this particular bios.

 

[Dougmeister]

I have the GA-MA78GM-US2H and it sounds like our overclocking options are pretty much the same. The number you need to increase that everyone is calling "HT Reference clock" is called CPU Host Clock Control in this particular bios.

Thanks. That's half of the puzzle.

Increase the HT reference clock to make the CPU and RAM faster.
Decrease the memory multiplier so the RAM doesn't run beyond its rated speed.

Now where is the memory multiplier hiding?

Is it the Set Memory Clock setting?

(DDR 400, DDR 533, DDR 667, DDR 800)

 

[Athadeus]

Yes, the Set Memory Clock setting is letting you choose your memory multiplier, just displaying the result as the product of the CPU Host Clock Control * memory multiplier.

edit: And as others said, it probably won't update the values listed to reflect an overclock in the CPU Host Clock Control. If you choose 800 Mhz, but have the CPU Host Clock Control overclocked 25&#37; (250 Mhz = 200 Mhz * 1.25), then the motherboard will most likely attempt to run the memory at 800 Mhz * 1.25 = 1000 Mhz.

 

[Dougmeister]

..

 

[Dougmeister]

OK. Here goes...

HT Ref Clock: 200
CPU Speed = 2600 MHz (as rated by AMD)
Therefore the
CPU Multiplier =13

HT Link Frequency: 1000 MHz (as reported by CPU-Z)
Therefore the
HT Multiplier = 5

And finally, if
Memory Speed is 800, then
Memory Multiplier = 4

Overclock

1) Keep CPU multiplier at "AUTO"
2) INCREASE HT reference clock ("CPU Host Clock Control") to make CPU and RAM faster
-> I can manually type in any value between 200 MHz and 500 MHz
-> 233 x 13 = 3029 (CPU Speed)
-> 233 x 5 = 1165 (HT Link Frequency)
-> 233 x 4 = 932 (do I need to lower the "Memory Multiplier"? If so, how?)

3) DECREASE Memory Multiplier ("Set Memory Clock") so RAM doesn't run beyond its rated speed
-> I have the following options: 400, 533, 667, 800
-> If I pick 667, does that change the multiplier somehow?

Can I go this high?

-> 266 x 13 = 3458 (CPU Speed)
-> 266 x 5 = 1330 (HT Link Frequency)
-> 266 x 4 = 1064 (Memory Speed)

I'd go higher, but I don't know how to lower the Memory Multiplier...

How about this?

HT Ref Clock | CPU x| HT x| Memory x| CPU Speed | HT Link Freq | Mem Speed
200.................13.....5............4............2600.............1000............800
233.................13.....5............4............3029.............1165............932
250.................13.....5............4............3250.............1250...........1000
266.................13.....5............4............3458.............1330...........1064

But this it bad (puts the Mem Speed too high):
300................13.....5............4............3900.............1500...........1200

So what if I change "Set Memory Clock" to 667?
Will this change (?) the multiplier to 3.3 instead of 4?

300.................13.....5...........3.3.........3900..............1500...........990

 

[Jovec]

How high you can go is a function of the quality of your individual CPU, mobo, PS, RAM, cooling, etc. Since this seems all fairly new to you, you I would start small and test for stability and temperatures along the way.

Realistically I would say that 240/250 max on the HT ref clock is what you can expect. Note that we really haven't talked about voltages yet, which is something you should understand too before trying to overclock too heavily.

You are correct about setting the memory clock to 667 to lower the multiplier to 3.33.

 

[Dougmeister]

Thanks. I'll give it a go later this evening.

I would say that 240/250 max on the HT ref clock is what you can expect.

Without adding a better heatsink (fan), liquid cooling, etc.?

Note that we really haven't talked about voltages yet, which is something you should understand too before trying to overclock too heavily

Yes, I noticed that was conspicuously absent from the discussion. From the little I know, I think you can push a little more juice to the CPU to make it faster. Is that right?

 

[Dougmeister]

OK. I tried setting the "CPU Host Clock Control" to 250. Kept rebooting. Tried 233, then 220, kept locking up. Tried putting the "Set Memory Clock" back to 667 MHz on all, none seemed to help.

Any last ideas? Otherwise, I'm at the end of my rope. Thanks.

 

[Wizlem]

Change all settings back to stock then on the main bios screen, hit <ctrl><f1> like you mentioned before. For my motherboard, this opens the ability to change dram timings. Change the timing setting from auto to manual but don't change any of the individual timing. This should keep the board from trying to use lower timings when you switch to 667MHz. Now set Memory Clock at 667 and HT Link at 800 and increment CPU Host Clock Control up starting at 220 and going from there by 5 or so. Might be able to take it to 240 or so. I have an Athlon II on my motherboard so I'm only translating what I did. Additionally, you may want to up your DDR2 Voltage to 2.1(max for this board) since its rated at 2.2 and try keeping memory set to 800 and adjust timings to rated specs.

 

[Dougmeister]

Ok, that worked. Not sure if it's any faster or not. What's a good benchmark program? I ran "Performance Information and Tools" from the Control Panel in Windows Vista before and after. The only Processor (calculations per second) went from a sub-score of 5.2 to a sub-score of 5.3. I have no idea what that means other than a slight (?) increase.

Additionally, you may want to up your DDR2 Voltage to 2.1(max for this board) since its rated at 2.2 and try keeping memory set to 800 and adjust timings to rated specs.

Do you mean:

System Voltage Control:
- DDR2: normal, +0.1v, +0.2v, +0.3v?

I can increase it by these amounts.

and try keeping memory set to 800 and adjust timings to rated specs.

I guess you mean "Set Memory Clock" to 800 MHz, but I'm not sure what you mean by the rest. I *think* you are referring to this blurb from the RAM I bought on Amazon:

"Runs at 1066 MHz CL5 with 5-5-5-15 timings at 2.2 volts"

But what does that mean? They are settings in the BIOS somewhere, but I guess it is different for each BIOS. I'm gonna reboot and look...

 

[Wizlem]

the default setting for ddr2 voltage is 1.8, setting it to +0.3 will put it at 2.1. Since your ram is rated to run at 1066 at 2.2v you should be safe running it at 2.1v with 5-5-5-15 timings and something a little lower than 1066. If you hit <ctrl><f1> to open dram timings option, they should be the first 4 options to change(I think). You might want to find a little more info on memory timings if you are unsure. Changing "Set Memory clock" to 800 with "CPU Host Clock Control" less than 266 should keep your memory running under 1066MHz.