So guy's this topic is still floating around some of the forums just to settle everything
Much longer answer:
A few weeks ago, I decided to try and settle this question once and for all by asking Intel. They finally responded officially yesterday.
However, in the meantime while waiting for them to get back to me, I found out all I could by checking the specs on their own H77 motherboards.
I discovered, in looking at the manual for the Intel DH77EB motherboard:
http://www.intel.com/support/motherboards/desktop/dh77eb/sb/CS-033188.htm
Quote
3.11 BIOS Performance Features
The BIOS includes the following options to provide custom performance enhancements when using 3rd generation Intel Core processor family and 2nd generation Intel Core processor family processors in an LGA1155 socket.
Processor Maximum Non-Turbo Ratio (processor multiplier can only be adjusted down)
Memory multiplier adjustment
Memory voltage adjustment
Graphics multiplier adjustment
So you can play with the multiplier (... and possibly downclock only, from reading that para in the manual...) but the big thing I noted is that you can't adjust voltages.
Not being able to adjust voltages is a big problem if you plan on overclocking, and doubly so for Ivy Bridge given what happens to IB processors temp-wise above 1.3V.
Finally I did get an official response from Intel yesterday and they confirmed that the following statements are true:
1. You can overclock and ivy bridge processor, on a H77 motherboard.
SO for example, if you own an i5-3570K, you can change the unlocked multiplier to from the factory value 34 to 45, to achieve an overclock of 4.5GHz (for example).
2. You CANNOT overclock a sandy bridge processor beyond the factory-set turbo multiplier.
So on the i5-2500K you can increase its clock speed to its max turbo frequency of 3.7GHz but no further.
see the i5-2500k Spec here: http://ark.intel.com/products/52210 factory clock speed is 3.3GHz, up to a max of 3.7GHz turbo
You can see the official response to my question from Intel here:
http://communities.intel.com/message/156063#156063
In theory the answer for your two questions is yes but Intel's position is that the operation of any Intel-manufactured product outside the published specifications for each part, such as overclocking, can result in data corruption and unreliable system behavior. It will shorten the life of your product, void the warranty of your processor, your motherboard, and possibly other devices installed in the computer. There is no support from Intel for overclocking.
To summarise:
Much longer answer:
A few weeks ago, I decided to try and settle this question once and for all by asking Intel. They finally responded officially yesterday.
However, in the meantime while waiting for them to get back to me, I found out all I could by checking the specs on their own H77 motherboards.
I discovered, in looking at the manual for the Intel DH77EB motherboard:
http://www.intel.com/support/motherboards/desktop/dh77eb/sb/CS-033188.htm
Quote
3.11 BIOS Performance Features
The BIOS includes the following options to provide custom performance enhancements when using 3rd generation Intel Core processor family and 2nd generation Intel Core processor family processors in an LGA1155 socket.
Processor Maximum Non-Turbo Ratio (processor multiplier can only be adjusted down)
Memory multiplier adjustment
Memory voltage adjustment
Graphics multiplier adjustment
So you can play with the multiplier (... and possibly downclock only, from reading that para in the manual...) but the big thing I noted is that you can't adjust voltages.
Not being able to adjust voltages is a big problem if you plan on overclocking, and doubly so for Ivy Bridge given what happens to IB processors temp-wise above 1.3V.
Finally I did get an official response from Intel yesterday and they confirmed that the following statements are true:
1. You can overclock and ivy bridge processor, on a H77 motherboard.
SO for example, if you own an i5-3570K, you can change the unlocked multiplier to from the factory value 34 to 45, to achieve an overclock of 4.5GHz (for example).
2. You CANNOT overclock a sandy bridge processor beyond the factory-set turbo multiplier.
So on the i5-2500K you can increase its clock speed to its max turbo frequency of 3.7GHz but no further.
see the i5-2500k Spec here: http://ark.intel.com/products/52210 factory clock speed is 3.3GHz, up to a max of 3.7GHz turbo
You can see the official response to my question from Intel here:
http://communities.intel.com/message/156063#156063
In theory the answer for your two questions is yes but Intel's position is that the operation of any Intel-manufactured product outside the published specifications for each part, such as overclocking, can result in data corruption and unreliable system behavior. It will shorten the life of your product, void the warranty of your processor, your motherboard, and possibly other devices installed in the computer. There is no support from Intel for overclocking.
To summarise:
- You can utilise the unlocked multiplier on H77 motherboards if you have an ivy bridge "-k" chip (3570k, 3770k)
- you cannot utilise the unlocked multiplier on non-ivy bridge CPUs (e.g. 2500k, 2600k, 2700k).
- you are not guaranteed to be able to control the VCore voltage ymmv depending on the mobo manufacturer and BIOS, but the intel H77 spec and their boards do not allow VCore voltage control). For this reason I would strongly advise against overclocking even ivy bridge CPUs on h77.
- unless someone who has bought a H77 mobo can confirm with pictures of the BIOS that their product they purchased allows VCore voltage manipulation...