OCZ Reaper X 1000mhz DDR2

Scott Salisbury · 2 Mar 2008 at 09:22

Hey all,

I've just got my new system up and running:
- Q6600
- 2x2GB OCZ 1000MHZ Reaper X DDR2
- ASUS P5KC
- 1x 8800GTX

When I set up the system, at default the memory is clocked at 2x400(800mhz), which obviously works fine, but because the memory is advertised at 1000mhz, I'd be happier to run it at that speed. I don't know an awful lot about overclocking, but I understand the basics.

I can't for the life of me get it to run at 2x500(1000mhz), I'm not sure what I'm doing wrong. I've disabled C1E and increased DRAM voltage to 2.1v as recommended by OCZ.

At the moment, I've got the system running at 2x400(800mhz) at 2.8GHZ with a 4:5 cpu:ram ratio, whenever I try to get the memory close to 1000mhz, it just doesn't like it, whether the cpu is running at stock, underclocked or overclocked.

Any ideas?
Thanks in advance.

RizlaKing · 2 Mar 2008 at 13:50

I am not 100% on this but i think one of the limitations of the P5KC is that it does only run ddr2 at a max of 800mhz. Hopefully someone a bit more knowledgable will be along to either confirm that or give you another reason.

Scott Salisbury · 3 Mar 2008 at 15:30

Hmm interesting. Seems a bit weird though, why is it limited to 800mhz?

Darryl_1983 · 3 Mar 2008 at 16:02

According to the info on OcUK the mobo should run 1066:

http://www.overclockers.co.uk/showproduct.php?prodid=MB-243-AS&groupid=701&catid=5&subcat=913

maybe try increasing the northbridge voltage by 0.1v and the fsb by 0.1v, i wouldn't go any further than that though.

Schnippzle · 3 Mar 2008 at 16:15

Would also make sure that the timings are set correctly at 5 5 5 18. I have this ram and its currently running at 1059mhz (I think).

Ezyryder · 3 Mar 2008 at 17:25

My memory is running at 1020Mhz 5-5-5-15 happily at 2.0v

Scott Salisbury · 3 Mar 2008 at 18:41

After some research, it has nothing to do with the memory, it's an issue to do with the tRFC value in the bios on the ASUS P5KC.

The board doesn't properly allow timings for 2GB DDR sticks at this speed, and the value that needs to be changed can't be reached in the bios without a workaround.

According to a moderator on official OCZ forums, this is the fix for the board but I haven't tried it yet:
- http://www.ocztechnologyforum.com/forum/showthread.php?t=34650

This might help anybody else with this mainboard/memory setup.