View Full Version : OC help - two sets of 6x2GB DDR-3 killed any oc'ing

11-05-09, 04:42 PM
I meant to title "two sets of 3x2GB" - pardon. The other day I bought two sets of CORSAIR DOMINATOR 6GB (3 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600. I know I should have gotthe matched set, but I got an amazing deal. I knew going in, I might have a problem going past 1333Mhz.

My motherboard is a Gigabyte GA-EX58-UD4P (I went i7 early - the UD4P is no longer sold I think). The memory is rated at 1.65v and this motherboard steps from 1.64v to 1.66v. So, I've been on 1.64v and haven't tried 1.66v. I'm actually not sure yet what's safe to try - memory voltage wise.

At default CPU speeds, 1333Mhz works perfectly at 1.64v. 1600Mhz seemed to work perfectly but 15 minutes into Memtest+ I got a spontaneous reboot (no errors though just a reboot).

Previously, I had my i7 at 3.8Ghz (air cooling - 3.8Ghz was rock stable). Now at 1333Mhz on the memory with 1.64v, I can't overclock at all. Even with a small increase (say 2.8Ghz) the BIOS will cycle twice and then report a failure and return the CPU to defaults. I actually tried a 2.8Ghz OC with the memory at 1066Mhz and I still had a BIOS reported failure.

So, I'm missing 1600Mhz (which may not ever be possible with 2 sets I know), and I've lost the ability to overclock even a little bit. I did try raising the Vcore and Vtt up a very good deal and it didn't seem to help. Previously, I could get 3.8Ghz with only a small vCore increase. I don't get why memory (even underclocked) would throw off a CPU overclock this badly.

Over the weekend I'm going to really make a serious attempt at this. What do ya'll think? Mostly about the RAM voltage... will 1.66v be safe, or would even a little more be safe?Thanks for any tips... I was really ready to take 12GB @ 1333Mhz, but I'm not going to be able to live with a default clock 920.

Edit: Just FYI because 12GB does seem insane. I do a lot of Premiere CS4 Pro and After Effects CS4 work. Even though they are 32bit applications, rendering video will take FULL use of 12GB and it does help a lot with render times. 12GB does give me a good advantage for day to day use.

bob saget
11-05-09, 05:53 PM
Nice motherboard, I have the same one. I may also have the same memory, not sure which model you have. I have a problem with mine though, and I was wondering if I RMA, which one would they send me.

I know 12gigs dont really like to be overclocked as much as 3 or 6, so you may hit some snags there. Try out this site. the guys on there specialize with gigabyte stuff (in the gigabyte section) and are VERY helpful.

11-05-09, 06:10 PM
Thanks, I hadn't been there before.

Yeah, I love this motherboard. Until now, I haven't had any problems with it at all and it has about everything you can ask for. The CMOS reset switch on the connector plate for the rear of the case is awesome. Actually on two occasions I've used the CMOS reloaded feature (backup CMOS). I can't imagine buying a board that doesn't have that built in now. I've had to wait a week for a BIOS chip to come in the mail before.

The only things it's really missing I could think of are WiFi (don't need) and a BIOS POST LED read out on the MOBO. That and it does have SATA connectors that point out sideways instead of up (which are a pain in the butt with the MOBO installed).

But, I've been building my own systems since 1996 and this is my favorite overall board. Next time around I'll really be leaning toward another Gigabyte. This was my first one.

bob saget
11-05-09, 10:57 PM
same, my first gigabyte too. My next one will be either a Gigabyte or EVGA.
Their California tech support is really really stupid though :(