Best Memory for Overclock?

RobHague · 4 Jan 2009 at 15:39

I bought an Ultima OC HD4870 (think that was the label) system from OcUK about 5 months ago.

It was pre-overclocked (358x9) -but in the system config (at the time of purchase) it said it was overclocked to 3.3Ghz +, but when all 4 slots were full the Oc was droped to 3.2Ghz. Since i ordered it with 4GB or RAM, all the slots were full so it came clocked at 3.22Ghz.

It has Corsair XMS2 Dominator PC8500 in it at the moment (4 x 1GB sticks).

I'd be happy with 3.3Ghz -im just after the speed it would have been had i got it with 2 sticks of DDR instead of 4 at the time. Am i right in thinking that OcUK would have used 370x9 (3.33Ghz)?

Maybe someone from OcUK could help there? =)

95thrifles · 4 Jan 2009 at 16:15

If youre happy to you can just go into the BIOS and up the OC yourself, you can prob get 3.4 easy, maybe 3.6

RobHague · 4 Jan 2009 at 20:17

I have been trying to find out if there is some issue with the IX38 QuadGT and having all 4 banks full, like instability or something. Must be a reason why OcUK said the OC was droped to 3.2 when u choose to fill all 4 banks?

Though ive been working something out, if the FSB is 358x9, then the RAM (PC8500) is only going at 716Mhz. Seems quite lax, unless im mistaken.

Been a while since i ventured into Overclocking (like Athlon XP 1700+ while) XD

Duke · 4 Jan 2009 at 20:23

Just put the northbridge voltage up a notch and it should be fine back at 3.4GHz+

RobHague · 9 Jan 2009 at 18:38

Ok, so i took a look in the BIOS to see whats what. Seems the memory is set to 1:1.25 so its going at (DDR895)

That's what it shipped with. I'm not sure why they wouldnt have set the FSB to something higher (say 366) and kept the DDR at 1:1? Is there any performance gained from running the DDR higher than the FSB? It's my understanding that there wouldnt be.