• Competitor rules

    Please remember that any mention of competitors, hinting at competitors or offering to provide details of competitors will result in an account suspension. The full rules can be found under the 'Terms and Rules' link in the bottom right corner of your screen. Just don't mention competitors in any way, shape or form and you'll be OK.

How far can I push this elpida vRAM?

Ripshod

Ripshod

Ripshod

Associate
Joined
17 Feb 2010
Posts
699
Exactly as the title. I bought a HIS HD7950 3GB FAN and it has this elpida ram.

I've seen it slated as a bad clocker so I'm wondering just how far I can push it. It's currently bench stable at 1400MHz/1625mV
 
Ripshod said:
Exactly as the title. I bought a HIS HD7950 3GB FAN and it has this elpida ram.

I've seen it slated as a bad clocker so I'm wondering just how far I can push it. It's currently bench stable at 1400MHz/1625mV
Click to expand...

I found my 7950's with Elpida would do around 1600mhz on their own. In crossfire it was about 1500mhz. Adding voltage did very little in terms of making them overclock further. Your mileage may vary.
 
I'll turn this topic into a sort of blog.

I did hit a limit at 1375@1600mV, the 1625 got me to 1400.

Peeps turn their noses up as soon as elpida is mentioned. I'm gonna test this particular set as I know quality changes throughout a single production run.
 
Last edited:
Ripshod said:
I'll turn this topic into a sort of blog.

Peeps turn their noses up as soon as elpida is mentioned. I'm gonna test this particular set as I know quality changes throughout a single production run.
Click to expand...

I know plenty of people that had crappy clocking (7950) Elpidas as well.
 
Its not that big of a deal unless you're pushing benches or ringing the most out of a really high res setup. I think a healthy average on 7950's was around 1450-1600mhz :)

Depends which reference design it is, most have a metal sink plate covering vram and vrm areas.
 
Anything more than 1400 seems to break openCL so I'm sticking there (not much of a blog I know).
Still it's better than 1250.

I know I don't benefit from extra ram speed when folding, and the info about some Hynix being the same has put a smile on my face, but to get this far I'm happy.
 
My final results are in.

You must understand I've had nothing but problems getting to this point (hardware errors, driver errors and software updates) a few of you will know of. Here's my results:

Started with default HIS HD7950 3GB AIR (reference cooler):
core: 825Mhz@1094mV
mem: 1250Mhz@1600mV

I now have (still with reference cooler @68C & 82%fan):
core 1100MHz@1125mV (AB limited for now)
mem: 1450@1625mV

Bench and stress stable. Will see what this does to my folding, but FAH estimates 125000+ppd at the moment. Will take an hour for it to settle. Running the 14.1 betas ;)

Strange that increasing the core frequency enabled another 50MHz on the ram??
 
Last edited:
Are these the same chips present on Hawaii (290/X) boards? I think they're rated for 1500MHz supposedly but many people can't hit that, at the very least they're very fiddly.
 
Tell me about it. They seem to vary wildly by batch. I can understand why people scoff at them, although some batches of hynix have the same problem, it's a lot worse with the elpida.
With the 290s being Hawaii based I'd assume the memory situation will be sorted somewhat. Are you sure they're elpida? (gpu-z will tell you)
 
Last edited:
I can hit 1250 / 1500 but this is with sapphire trixx, VDDA@200% and Power limit@+50. I got these setting from a youtube channel and a very helpful gentleman. Passed firestrike and valley haven. Only think is it hits 1.42V not sure what the safe voltage limit is on these cards (Sapphire R9 290 REF)
 
DMF1986 said:
I can hit 1250 / 1500 but this is with sapphire trixx, VDDA@200% and Power limit@+50. I got these setting from a youtube channel and a very helpful gentleman. Passed firestrike and valley haven. Only think is it hits 1.42V not sure what the safe voltage limit is on these cards (Sapphire R9 290 REF)
Click to expand...

Probably best to stay at +100mv maximum on reference air cooling. In crossfire i leave voltage at stock personally. Both my cards can do 1100 core on stock voltage.
 
Ripshod said:
I know some 'boost' bioses go as high as 1.25V, so I never go near that. My personal max ever on tahiti is 1.175V
Click to expand...

Tahiti can handle up to 1.25v without a worry and 1.3v is fine as long as temps are kept in check. 1.2v or lower if you like to play it safe. :)
 
I've still got room to move on the GPU, just AB crashes when I enable the extended facilities. I've tried Trixx and can't get the vCore to change.
 
You must log in or register to reply here.
Back
Top Bottom