Tom’s Hardware is a really good source we can definitely trust, so if you need more details on Radeon HD 5000-series cards (specifications and prices) that are coming soon, just read:

Best Graphics Cards For The Money: September ’09

Update (Sep 16th): GT300 could outperform the Radeon HD5870

Update (Sep 22nd): ATI Radeon HD 5870 pricing and specs list revealed

Update (Sep 23rd): ATI Radeon HD 5870: DirectX 11, Eyefinity, And Serious Speed