I've seen some wikis showing Radeon HD 7770 around 170-180Kh/sec but with these tweaks its up to 195Kh +
In Windows go into Catalyst Control Center, Performance, AMD overdrive, check enable graphics overdrive.
GPU Clock is set to 955mhz Memory set to 1500mhz (or 1365 read below)
cgminer --scrypt -I 16 --thread-concurrency 8000 -o stratum+tcp:..
I've tried higher and lower GPU clock settings but the hash rate goes down, maybe others can do better with tweaking and get it passed 200Kh.
On newegg the card is listed as GIGABYTE GV-R777OC-1GD Radeon HD 7770 GHz Edition 1GB 128-bit GDDR5
Here's picture of settings and dogecoin mining
http://abload.de/img/c77708lerh.jpghttp://abload.de/img/c77708lerh.jpg