If you have the HD8570 dedicated card around 86kh/s is what I was getting as well before any tweaks. But it sounds like you have the HD8570D GPU in an APU (Looks like they are in A8-6500 and A8-6600K CPUs) then you will definitely will be getting much lower kh/s than the dedicated card from looking at the specs. Since the GPU in the APU is sharing the system memory you will have to overclock your RAM in your motherboard BIOS settings.
Just in case you are talking about the dedicated card or someone else finds this thread I was able to get 127Kh/s with these settings.
SGminer 4.0.0 settings:
"--gpu-platform 0 -d 0 -w 256 -I 16 --lookup-gap 2 --thread-concurrency 3200"
This tweaked OpenCL file got me about 1% more kh/s and works for many cards. There are also others out there to try.
System:
Windows 8.1 with AMD 13.9 drivers
GPU Overclock:
Core clock from 780mhz to 990mhz
Memory clock from 900mhz to 1155mhz

yes, it is infact inside an APU, AMD A8-6600K is it safe to overclock RAM? I don't want to insta-fry my new memory – ZCoder – 2014-01-27T23:17:36.970
Overclocking memory is pretty safe, overvolting is where the bigger risk comes in. Just make sure run Memtest86+ after changing any RAM settings. If you boot into your OS with bad memory setting you can corrupt your OS and/or any files you save. I would be very surprised if you get over 50 Kh/s with that GPU and would be actually losing money after you take into consideration the cost of power. Mess around with the setting just to learn.
Do research, then ask questions, get a dedicated card if you want to get into mining but remember there is a risk that you won't make your money back. – jkasten – 2014-01-27T23:42:27.853
Memtest86+ has never worked right for me for some reason. it doesn't seem to matter what type of RAM or CPU, there was always something off about the specs, with the exception of one time it reported the memory correctly and even passed the tests even though there were obvious defects in the memory(of course not the set I'm using now) :/ – ZCoder – 2014-01-27T23:45:36.953
Memtest86+ has been reliable for me as far as detecting bad memory. I have seen the FSB, CPU type, etc not show correctly many times but that doesn't effect the test themselves. If you really want to make sure memory is good let it run over night so it does 3 or more passes. Also make sure you have the newest BIOS for your mobo. I have seen good RAM just be flaky due to a BIOS bug that affects only some RAM – jkasten – 2014-01-28T00:11:54.807
could be. for the current system MT86 says my ram is DDR1 running at 250Mhz, which is way off. both the bios and windows are able to retrieve the correct timings,however. – ZCoder – 2014-01-28T00:23:35.563