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RamzesXXXII
12-16-04, 02:03 PM
I bought PixelView GF 6600 Ultimated 256 MB and I overclocked my vga GPU to 480Mhz but I'm afraid to overclock memory ( I set it to 525 Mhz). What type of memory has that card (what is it maximum clock freq ??) ???

Salamandar
12-16-04, 05:29 PM
I bought PixelView GF 6600 Ultimated 256 MB and I overclocked my vga GPU to 480Mhz but I'm afraid to overclock memory ( I set it to 525 Mhz). What type of memory has that card (what is it maximum clock freq ??) ???

Best thing to do is to overclock by a 5MHz then play some games, if you don't see any white dots , black dots or corrupted textures then over clock by another 5 MHz and so on until you see the white dots , black dots or corrupted textures.
When you see them reduce the clock a little until they disappear.
Good luck.

Rytr
12-16-04, 07:10 PM
It helps if you know the speed rating of the ram as designated by the Mfg. It is listed on the ram chip as something like '36' for 3.6ns ram. If it's not clearly marked you can get the batch number off the chip and go to the mfg's web site and cross reference it to find out the specifics about the ram.

If the ram is rated at 3.6ns you can find the theoretical speed rating in MHz by simply dividing 1000 by 3.6 which gives you 277.78 (which is more commonly rounded off further and referred to as 275 or 275MHz). For double data rate (DDR) ram you multiple that figure by 2 which gives you 555.56 (or again, more commonly referred to as 550 or 550MHz). This is the theoretical speed rating assigned by the mfg. in MHz (550) the same as the nanosecond (ns) rating of 3.6. Any clock achieved over 550MHz would be considered an overclock.

In a recent review, I had a card with 3.6ns SD DDR ram. I was able to exceed the 550MHz rating and go to 600MHz but I experienced light artifacting in 3DMark2003. I backed off the overclock to 575MHz and the ram has displayed stable performance since. I normally back off 20-25MHz when establishing a stable overclock once artifacts show up. You probably can get the same stability by backing off 10-15MHz. I just opt for being a little more conservative, insuring a more potentially stable overclock of the ram.

Note: all ram is not created equal as my overclock of the above ram shows. :( I was hoping for 625 to 650MHz but no dice...

RamzesXXXII
12-17-04, 05:11 AM
I have Samsung 346 ( K40551638D-TC40 ) memory so it is 4.0ns memory. Maximum clock is 500Mhz. But I heard that somone overclock it to 700 Mhz
it is possible ???

Rytr
12-17-04, 03:59 PM
It is possible but highly unlikely. As I said, not all ram is created equal and it's always worth a try. If you try just up the MHz slowly in small increments, testing at each new setting. If and when you encounter artifacts, stop and back it off at least 10MHz. That will probably be you best overclock setting for the ram.
In the new games I have usually achieved more performance per MHz with the overclock on ghe gpu as compared to the overclock attained on the ram.