Originally Posted by MikeBMW
OK, so I'm planning to buy 7970 or 680 but my questions are:
- some guy said "just buy the reference card" , what did he meant by this?
- how do I know if the card is locked?
- some cards have OC in the name, so they are already OverClocked or the are capable of OverClocking
- someone wrote "non-OC generic cards", what he meant? is it good or bed
- do 7970 have to be over 1000Mhz to be better to overclock,
I will play with overclocking, and I will probably add some water blocks.
1.) By a reference card, he was referring to a card that has a PCB that is unmodified from the OEM version. Meaning the OEM PCB has not been modified.
2.) On the latest generation, locking refers to voltage adjustments. This is based on the manufacturer and does not apply to all cards, some research will be needed to determine which cards are lock and which are not.
3.) Generally speaking OC cards are GPU's that are guaranteed to have a preset value set for whatever parameters the manufacturer sees fit. Sometimes this means the card is a higher binned product, although this is not always the case.
4.) Non overclock cards are just versions that have not been verified at a higher setting. So lets say the overclock version has a setting of 1050 core, 1250 memory. The card has been verified to work at these settings. A non overclock card has to be verified to work at the OEM specifications, which is always less than the OC versions of the same card. Sometimes you can get a non OC version to overclock higher, but its a gamble.
5.) Simply stated no, the "GHZ" is mainly a marketing gimmick. While the cards sold as GHZ editions have to be verified to operate at 1000mhz, it does not always indicate that these chips are superior from the non GHZ edition cards. I believe what may have happened here is that the card manufacturers realized that it was relatively easy to achieve a core speed of 1000mhz , and started selling the cards that could achieve this speed as the GHZ edition to make it seems as if these cards were better than the prior iteration. Whether or not there was any improvement in the manufacturing process is unclear.