Posts Tagged ‘overclocking’

Overclocking Q6600 on P5B Deluxe

March 20, 2012

There are hellova articles in the Internet on OC in general and particularly on overclocking CPUs on ASUS P5B Deluxe and other P965 chipset motherboards.  So here I’ll just post my results and BIOS configuration, along with some of my findings.

I was able to overclock FSB from 266 to 400 with x8 CPU multiplier. Which effectively means 3200MHz frequency as opposed to 2400 stock.

BIOS settings

JumperFree Configuration

CPU Frequency: 400
DRAM Frequency: DDR2-800MHz
PCI Express Frequency: 101
PCI Clock Synchronization Mode: 33.33MHz
Spread Spectrum: Disabled
Memory Voltage: 1.9V
CPU VCore Voltage: 1.525V
NB VCore: 1.25V
SB VCore (SATA, PCIE): 1.5V
ICH Chipset Voltage: 1.057V

CPU Configuration

CPU Ratio Setting: 8
C1E Support: Disabled
Max CPUID Value Limit: Disabled
Vanderpool Technology: Enabled
CPU TM Function: Enabled
Execute Disable Bit: Enabled

North Bridge Configuration

Basic Timings: 5-5-5-15-5
Additional Timings: 42-10-10-10-25
Static Read Control: Disabled

The most important thing to realize about OC on P5B Deluxe is the necessity of manual memory timings set up. Initially I wasted a lot of time trying to OC over 350 FSB with no luck. After changing timings to mentioned above I easily OCed to 400. I can’t explain why you need to set them like this. I just found them in the Internet and it works for me.

What was also new for me is that CPU with x6 multiplier and 400 FSB won’t work with the same voltage as x9 on 266. It’s the same frequency, however, CPU always init on x9 multiplier and only after power up system changes it to configured in BIOS. It means that if you want to lower CPU voltage by changing multiplier, then don’t expect voltage to decrease to initial values.

Another interesting fact is that with C1E Support setting enabled you will get less performance and less marks in CPU dependent benchmarks like 3DMark. C1E Support can lower CPU frequency when CPU idles. But it seems that it also reduces its performance under load.

I also left CPU TM Function (throttling) enabled for safety purposes.

For those who want to increase FPS in games I want to say that CPU and memory OC won’t give you any significant performance boost in games. For example in Unigine benchmark for 266 FSB, 2.4GHz CPU I get 37.9 average FPS. And for 400 FSB, 3.2GHz I get 38. I agree that for some games it will make difference but it’s not worth it. Don’t torture your system.


266 FSB, 2.4GHz CPU:

Max temperature in linpack (OCCT) 54C (measured by Core Temp)
SiSoft Sandra Memory Throughput 5Gb/s
3DMark’06 12211
Unigine Heaven 37,9 avg. FPS
1:10 hour HD video encoding 3:47 hours

400 FSB, 3.2GHz CPU:

Max temperature in linpack (OCCT) 87C (measured by Core Temp)
SiSoft Sandra Memory Throughput 6.45Gb/s
3DMark’06 14945
Unigine Heaven 38 avg. FPS
1:10 hour HD video encoding 2:59 hours

As you can see I have extreme temperatures in linpack, even though I have Thermaltake Big Typhoon VX cooler and efficient Arctic Cooling MX-2 thermal grease. However, you should understand that system never gets to these temperatures under standard system loads like gaming, video encoding, etc. Usually I get no more that 65-70 which is not that high.

Bare in mind that P5B Deluxe undervolt your CPU by 0.5V. It means when you set VCore to 1.525 it’s actually 1.475. Also when I set VCore higher than 5.125 (1.465 effective) motherboard automatically changes VCore voltage to Auto. In fact, it will work on set up voltage until you enter BIOS and save changes for the second time. In other words if you set voltage higher than 5.125 then you will need to set it again after you enter BIOS and change anything for the next time.

The main reason for me to OC my system was video encoding. Firstly I changed old 2 core E6300 to 4 core Q6600 and then OCed it. I used 1:10 hour HD video for testing purposes. Time has changed from 8:08 on stock E6400 to 3:47 on stock Q6600 and then to 2:59 on OCed Q6600. So performance increase is quite apparent and worth it for this class of tasks.


How much sense is in overclocking

February 9, 2011

Recently I’ve overclocked my home desktop from FSB 266MHz to FSB 400MHz. To estimate a difference I ran simple test – HD video encoding which is my frequent compute intensive task. I took short 1:16s HD video and converted it for YouTube:

400MHz FSB – 4:45s
266MHz FSB – 6:06s

Benchmark shows that 33% increase in FSB gives me 22% faster HD encoding. Is it reasonable? It’s up to you to decide.

Core 2 Duo overclocking

November 26, 2010


Everybody knows that Core 2 Duo is a perfect processor for overclocking. I have becoming legacy E6300 model. Since I also have 800MHz memory, P5B Deluxe motherboard which is a overclockers choice and TT BigTyphoon CPU cooler I decided to play a little with my FSB frequency.

Overclocking procedure

The reason why I started this in the first place was low 3DMark06 results – only 8600 points. I saw 12k for similar PC configurations.

On ASUS motherboard you can find overclocking tweaks under Advanced -> Jumperfree Configuration -> AI Tuning -> change to Manual. I locked PCI frequency at 33.33MHz and PCI-E frequency at 101MHz. Then I was able to increase FSB frequency from 266MHz up to 320MHz without any other tweaking in cooling or voltage. Then system started to become unstable: application crashes and BSODs. I used same 3DMark06 for testing purposes.

Next step was  replacement of poor North Bridge radiator with Zalman NB47J. I also sticked small radiators from my old Zalman VF700-Cu I took from a drawer onto unipolar CPU transistors which are always getting hot on P5Bs. It let me become stable with 340MHz. Next was updating a BIOS. I had old 0405 version. Surprisingly enough BIOS v1238 allowed me to increase frequency up to 400MHz! I think it comes from the fact that ASUS improved automatic voltage regulation in later versions. I stopped at this point because further increase of FSB will force memory modules to work at not-supported frequencies which I don’t want to deal with.

Overclocking results

parameter: old value, new value, %
memory throughput: 4.77Gb/s, 6.77Gb/s, 40%
cpu frequency: 1.86GHz, 2.80GHz, 50%
3dmark: 8600, 10600, 25%

CPU temperature and undervoltage

Unfortunately I got too high CPU temperatures. 68C idle and more than 84C under load. To solve this problem I changed thermal grease. It gave me 8 degrees. And lowered CPU voltage from 1.5 to 1.1 by 0.05 step. Beware of motherboard setting up VCore lower than you actually pointed on 0.05V. It means that if you set 1.35V you will actually get 1.3V. You can check that under Power -> Hardware Monitor after reboot. Each time I tested CPU with S&M ‘cache 1’ test. It gave me highest CPU temperatures. Then I launched OCCT (Overclock Checking Tool) 3.1.0. Its ‘CPU Linpack’ test just burns everything. But test ended with ‘Error Detected’ message. Increasing voltage by 0.05 solved the problem and test went just fine. After an hour of CPU burning Core Temp 0.99.8 showed me 40C idle and 51C load. It’s astonishing how motherboard overvolt CPU.

Additional info

FSB / Memory throughput:
266 MHz, 4.77Gb/s
320 MHz, 5.13Gb/s
340 MHz, 5.51Gb/s
350 MHz, 5.66Gb/s
400 MHz, 6.77Gb/s

Voltage / CPU idle and load temp:
1.5 59C/77C (S&M)
1.45 53C/68C (S&M)
1.4 51C/64C (S&M)
1.35 47C/60C (S&M)
1.3 45C/56C (S&M)
1.25 43C/54C (S&M)
1.2 42C/51C (S&M)
1.15 41C/48C (S&M)
1.15 40C/51C (OCCT)
1.1 39C/46C (S&M)