I have an HIS 4870 and since this morning, the fan is acting weirdly.. making huge rattling noise and it even stops spinning at times when my casing is in vertical.. (i.e. fan pointing downwards)... so i am searching for a new cooler/fan replacement for it.. a budget/cheap one for a quick fix as i am planning to buy a new highend GPU next year. if possible a cooler less than $30-35.... thx