low fps when increasing memory clock

i have a sapphire r9 285 2gb clocked at 918mhz core and 1375mhz memory. i started overclocking my card and i reached 1060mhz clock and 1500mhz memory with +20% power limit and no increase in voltage. All this was done using msi afterburner 4.0.0. To test the stability and temps i used furmark 1.14.1.4. At stock speeds it gave me 84 fps. At overclocked mode it gave me 91 fps with a increase of 2 degrees in temp. So i decided to overclock it more and bumped up the core to 1070 and it started showing artifacts in unigine heaven. I dont wanna increase the voltage so i kept it at 1060mhz clock. I then bumped the memory to 1550mhz and then again ran furmark and it was stable but the fps dropped to 86fps. I dont know what am i doing wrong here cos i am new to overclocking.
so these are the fps-
core memory fps
918 1375 84
1060 1500 91
1060 1550 86

all these fps are using furmark at 1280 * 720 res and no aa.

full system specs-
cpu-Core i3 2100 3.10ghz
motherboard- GIGABYTE GA-H61M-s1
ram-corasair vengeance 1300 mhz 6gb(4+2)
hdd-WD green 3 tb 7200rpm
gpu-Sapphire r9 285 dual x 2gb
psu-corsair cx 600
case- cooler master k380
monitor-LG flatron e2041

Not all that familiar with overclocking either but the only thing I can think of is thermal throttling. You said you had a temperature increase of 2 degrees, but what are those temperatures?

Too high memory clock may cause memory errors and slowing down due to corrections or driver is lowering clock. Memory clock is not helping much on these cards so I would focus on core clock. 10% higher voltage is usually safe limit for most computer parts.
Testing cards with furmark is not best idea. This soft is heating up cards more than it's necessary. Better run 3DMarks mixed with some other benchmarks or tests based on games.

MajorTemples said:

Not all that familiar with overclocking either but the only thing I can think of is thermal throttling. You said you had a temperature increase of 2 degrees, but what are those temperatures?

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at stock setting its 70 degrees and at overclocked setting its 72 degrees

Its likely the ECC on the memory is kicking in, lower the memory clock a bit...

Woomack said:

Too high memory clock may cause memory errors and slowing down due to corrections or driver is lowering clock. Memory clock is not helping much on these cards so I would focus on core clock. 10% higher voltage is usually safe limit for most computer parts.
Testing cards with furmark is not best idea. This soft is heating up cards more than it's necessary. Better run 3DMarks mixed with some other benchmarks or tests based on games.

Click to expand...

can u tell me how to increase the voltages or give me a guide or video link. i got a 100 watt headroom cos i have 600 watt psu and the gpu takes 500 watt. and can u tell me a software to check the total wattage usage of the whole system. thanks...

Software called MSI Afterburner can increase your voltage if the card allows it.

The videocard does NOT take 500W by itself. That is a recommendation for the ENTIRE PC. That is also not where your limit would be. In MSI Afterburner (and CCC) there is a power limit slider, be sure that is at the highest value.

THere isn't software that does it accurately, you need hardware to show that information... get a Kill A Watt.

You also have a weird system ram setup.. 6GB? Are they matching sticks or different? Personally, I would scrap what you have and buy 2x4GB. Mixing and matching ram can cause instability.

EarthDog said:

Software called MSI Afterburner can increase your voltage if the card allows it.

The videocard does NOT take 500W by itself. That is a recommendation for the ENTIRE PC. That is also not where your limit would be. In MSI Afterburner (and CCC) there is a power limit slider, be sure that is at the highest value.

THere isn't software that does it accurately, you need hardware to show that information... get a Kill A Watt.

You also have a weird system ram setup.. 6GB? Are they matching sticks or different? Personally, I would scrap what you have and buy 2x4GB. Mixing and matching ram can cause instability.

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i know the 500 watt is for the entire pc and i told in my 1st post that i have the power limit slider to max +20%. Thats why i need a software to check the total wattage and see how much headroom i got for overvolting.. Actually i dont how to use a multimeter to check the total wattage of the system..

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EarthDog said:

Its likely the ECC on the memory is kicking in, lower the memory clock a bit...

Click to expand...

i am getting the max fps at 1500 mhz memory if i go down to 1499 the fps decrease by 1 like 90 fps and if i increase the memory to 1501 then the fps is decreasing to 86 fps.. so 1500 is the best i think..

Your PC isn't close to using 500W friend. Your PSU is not a limit here and is not relevant in this discussion.

I didn't say check with a multi-meter. I said to buy a Kill A Watt (which plugs into your wall socket and your PC plugs into it).

Seems like 1500MHz is the max on the memory side without adding voltage to it (if that is possible, not all cards allow that).

EarthDog said:

Your PC isn't close to using 500W friend. Your PSU is not a limit here and is not relevant in this discussion.

I didn't say check with a multi-meter. I said to buy a Kill A Watt (which plugs into your wall socket and your PC plugs into it).

Seems like 1500MHz is the max on the memory side without adding voltage to it (if that is possible, not all cards allow that).

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thanks man. i will buy it soon. How much voltage should i increase at a time and test the stability?? how much clock should i increase after increasing voltage??

Try .05v and test. Raise it maybe 25Mhz then test with Unigine Heaven or something similar (not furmark). You really do not get a lot of voltage to play with on GPUs.

EarthDog said:

Try .05v and test. Raise it maybe 25Mhz then test with Unigine Heaven or something similar (not furmark). You really do not get a lot of voltage to play with on GPUs.

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ok man i will do it soon and let u know.. Does overvolting fries up the gpu?? Just in case u know..

There is always a chance when running it out of spec, sure. But as was mentioned earlier (maybe in another thread) 10% is a good rule of thumb.

To overclock/overvolt your card try manufacturer's software. Sapphire Trixx ( on driver's CD or Sapphire's site ) is usually working better than Afterburner. This soft has usually voltage slider limited to max safe values so you shouldn't burn your card. Cards nowadays have also overheating, overvolting and some more protections so it's really hard to kill them.

Woomack said:

Too high memory clock may cause memory errors and slowing down due to corrections or driver is lowering clock. Memory clock is not helping much on these cards so I would focus on core clock. 10% higher voltage is usually safe limit for most computer parts.
Testing cards with furmark is not best idea. This soft is heating up cards more than it's necessary. Better run 3DMarks mixed with some other benchmarks or tests based on games.

Click to expand...

Correct, GDDR5 memory is ECC which means when it produces errors it lowers clock to compensate. Thats why I usually dont bother OCing memory on video cards, its tricky.

The clocks stay the same AFAIK. Just that the actual error correction is what slows things down.

EarthDog said:

The clocks stay the same AFAIK. Just that the actual error correction is what slows things down.

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Yeah, thats what I read, I just never actually checked to see if clocks lowered or not but yes you right on spot.

The clocks stay the same (at least in the MSI AB graph/log). I've checked, and it doesn't budge.