how high can you guys clock your 7970 at stock voltage?

[SickBeast]

I have a gigabyte 7970 on the way and it is voltage locked at 1175mv. how high can you guys clock your 7970 at this voltage?

 

[Tempered81]

BEAST! Voltage locked!? WHA? hehehe You going to have watercooling?

I have 7950s not 7970s, but they are Gigabyte Windforce 3x. Different bioses give them varying stock voltages (locked and unlocked too ;p ) - F43 bios still being the best. 1175mv does about 1100-1180mhz, Asics are 60/68/69/78. None of mine go above ~1250mhz reliably with 1300mv stock air cooling. I keep them around 950-1000mv mining @ 75C, and 1250mv gaming @ 65-70C, 100% fan. I've ran benches @ 1310mhz on my best card and ~1160mhz x 4 in quadfire reaching the verge of stability just to achieve a high score, but in a long gaming session I usually stay at ~1250mv/1200mhz core with CFX disabled. Memory is adjustable 1500-1700mv in regular afterburner, or ~2000mv with a custom/hacked version. Bios can determine memory timings and default mvddc, so memory clocks can change too (even on same card with 2 diff bios) Core is capable of 1400mv without mods before OCP but IMO that is way too high without liquid cooling or better, unless it's just a quick bench. My card's weakness is VRM temp - shut down because of VRM temps being >115C or my PSU being overloaded. Have to keep a 140mm fan strapped to the VRM sections for benching. With some tinkering you may find a way to unlock the voltage. Just search your default bios string @ OCN or TPU and see what the community says is the best Bios. One of my 7950s is a different revision PCB with 6+6 instead of 6+8 and I flashed about 6 different bioses on it. None of them would show me VRM current load & temp, or correct vddc/mvddc, but F43 still gave me ~40% higher overclock than the rest of them and a false voltage readout even with a grayed-out voltage slider in afterburner. I guess its pushing 1.25 to the card, and showing 1.09 in GPUz, but the OC went from ~1020mhz to 1180mhz with just a different bios despite not having adjustable voltage, and not showing a change in voltage readout. Yeah quick search of your bios string and PCB revision/part # (ex: 015.024.000.002.000907 / HD 7950 GV-R795WF3-3GD) and you'll find somethin. Theres also tons of other quirky ish with these cards too - like core to memory ratios making a bigger impact on FPS & benches than just pushing a higher core - like 1488mhz memory giving higher score than 1600mhz memory depending on core: mem ratio. Or that some bioses throttle voltage & clocks and some do not... I tell yah, it's a friggin warzone. PM me and I'm happy to help find a good custom bios.

Even Nvidia's 'voltage locked' Gtx 680 & titan OCP limits have been circumvented without hardmods, and those PCBs have dedicated circuitry to stop over volting - which the Giga 7970 doesn't have AFAIK.

This is all assuming you want to mess with your card. I already fried one of mine, and warranty doesn't cover my overclocking, so im SOL. It has to go on Ebay "as-is for parts" or to someone who knows how to solder/repair ;p. If you plan to stay at 1175mv, I guess 1120-1200mhz, depending on (voltage being #1 variable) cooling, bios, timings, what you're benching, PSU, ASIC qual, and what your mem is at.

 

[Silverforce11]

My 7950 is stable in games at 1175mv at 1.2ghz, but needs 1200mv for bit mining stability over several days.

You should hit 1.1ghz easily with those vcore, probably 1.15ghz also.

 

[SickBeast]

Wow, thanks very much for that, Tempered81. I will send you a PM once I have the card up and running and once I know what BIOS version I have.

I was reading that these cards are indeed voltage locked at the hardware level and the only way around it is to remove a resistor and solder something else on there. If you know of a way around it with a BIOS mod I would really appreciate it.

 

[hawtdawg]

My 7950 is stable in games at 1175mv at 1.2ghz, but needs 1200mv for bit mining stability over several days.

You should hit 1.1ghz easily with those vcore, probably 1.15ghz also.

thats weird, my 6950's can get by on less voltage for mining than whats required for gaming

 

[blackened23]

If your card is voltage locked at 1175 or 1200mV you should be good to go. The only stop sign would be if GB locked the voltage "low" at sub 1100 mV, which I don't believe they do. Anyway, I remember my 7970s clocked past 1200ish at that range stable - but temper your expectations, as always overclocking is luck based. You may or may not have similar success.

If you're voltage locked high it shouldn't be a big issue, the only problems arise with being voltage locked "low" at sub 1100mV.

 

[jacktesterson]

My Asus 7970 did 1200 stock

My Diamond cards do 1150 stock 24/7

 

[Elfear]

My XFX Core would game all day with the stock cooler at 1225Mhz@1.178V.

 

[VulgarDisplay]

Mine would do 1125 at stock voltage in the winter, but this room is too hot and I have to tone it down to around 1080 to be truly stable in the summer months.

 

[Granseth]

I had mine run at 1150MHz at standard voltage and 1200MHz at a litle bit extra. The temperature have been at 64°C for most of the time.

 

[Greenlepricon]

My MSI 7950 was voltage locked really low at 1000mV, so it only hits 1015mhz completely stable. Pretty sad, so thank goodness for overvolting.