Lower FPS after overclocking HD Radeon 5770?

joshernater9

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Alright, well i wanted a bit of a performance boost, so i overclocked my graphics card with Afterburner. Default clock is 850MHz and Memory of 1200MHz. I bumped it up to 960 and 1400. I know i could probably go higher, but last time i tried i got a gray screen, so best to keep it safe..

anyways, this OC appears to be stable, except whenever i run a game, i have extremely low FPS. I tried running Assassins Creed: Brotherhood, and i was getting probably around 5-13 FPS. I tried it out on Skyrim to make sure it wasn't the game, and again it was extremely low frame rate. Both these games ran fine before the overclock, So its odd that its a decrease..Any ideas?


System Specs:

AMD Phenom II X4 955 Processor 3.21 GHz
RAM: 8.00GB
ATI Radeon HD 5770 Series
Windows 7 64-bit
 
Solution
When you bump VRAM speed too high you lose performance. GDDR5 can sort of resend data if it fails, which causes a big slow down. Drop that mem clock to 1350 and see what happens.

joshernater9

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Thanks man, that seemed to do the trick :D
 

joshernater9

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Crud, Guess i spoke too soon..I was playing Assassins creed and the game froze and there were black lines everywhere..I get very good temps..I barely break 50C when my fans are going between 80-90% power...Any suggestions?
 
Hmm. Could be core or VRAM. Since lower the VRAM improved performance, I'd say this time try dropping the core a little. Temps aren't so important if they aren't getting enough juice. Try 950 core first, see what happens. If your GPUs allow it, you could also raise voltage but I suggest trying to see what the max stable clocks are at stock first.
 

joshernater9

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Yep, that was the lucky number ;) thanks!