Mac Pro 8 core + ATI Radeon HD 5870 very slow GPU after sleep
Hi,
I recently 'invested' in a HD 5870 for my Mac Pro 3,1 (OS X 10.7.2, Dual Quad Core Xeon 2.8 Ghz, 8 GB ram). It's a fantastic card and makes a big difference to FCP and gaming. HOWEVER. I've noticed a MAJOR issue, if you put the Mac Pro to sleep then after waking the GPU seems to function at one fifth normal speed. I've repeatedly proven this and have even managed to measure it using LuxMark (http://www.luxrender.net/wiki/LuxMark).
After a clean boot my LuxMark results are respectable:
Clean boot - 4299 (GPU only), 7130 (CPU+GPU)
However, after sleep / wake-up:
After sleep - 864 (GPU only)
And you can REALLY feel that slowdown, windows paint slowly, scrolling stutters. (Games are unplayable, only a reboot resolves).
Anyone else seen this issue / have any recommendations?
Mac Pro / MacBook Pro, Mac OS X (10.5.7)