I have a canon powershot SX20 IS i have dropped it. to start with my large lcd screen shows just grainy white but i could still see through the small eye lens screen. but now i have lost the projected picture in both screens now. could this be a loose wire or does anything need replacing. i first thought it was just the large screen so i took it apart to see if there was any visible damage but nothing i put it back together and it was working just on the small screen still after a while the white spead to the small scrren so this makes me think its something internal. please advise

Does it still shoot photos "in the blind?" No, I do not know what is wrong. If you were to have said only the LCD screen was broke, that can often can be an easy do it yourself fix. There is a company on ebay, I think there store is in Illinois, that sells brand new screens for only 15 bucks. On youtube there is video that shows the surprisingly simple repair. Only tool you really need is a super tiny phillips screwdriver, one small enough for eyeglass repair, and be darned careful not to lose the tiny screws! But in your case the repair may or may not work because you say the viewfinder also is on the fritz. Best of luck.

you need to replace the lcd, has a look here.

The wires that go through the pivot point to the LCD may be damaged by use or the switch that detects the position of the LCD unit may be bad

check lcd connection & clean.if ok flash software.

Press the FUNC/SET button. Use up/down to select "My Colors" (the palette, second item from the top). Use left/right to select "B/W" for black-and-white then press FUNC/SET.

Can I shoot B&W pics with my new Canon PowerShot SX20-IS?

There is a small knob to adjust the image through the view finder.

Refer to the manual if you cannot find it.

Check the diopter adjustment on the left side of the viewfinder.

This sounds like it might be a defective CCD imager. If so, Canon should fix this for you for free, including free shipping both ways. This is regardless of your camera's warranty status. Please check the following two links for more info:
　
http://camerarepair.blogspot.com/2007/11/canon-digital-cameras-showing-black.html
　
http://www.usa.canon.com/consumer/controller?act=PgComSmModDisplayAct&fcategoryid=225&modelid=13390&keycode=2112&id=29819

Applicable cameras include:
A40, A60, A70, A75, A80, A85, A95, A300, A310, S1 IS, S60, S200, S230, S330, S400, S410, S500, SD100, SD110, IXUS V2/300/400/430/500, IXY Digital 200a/300a/400/450/500

Hi: I think you have broken (accidentaly with the fall) the cable with several wires that connect the LC display. My real advice is that you take your camera to a store were they can give you direct support desmanteling the camera and replacing the cable or fixing it. However, Zair already had a problem like yours and the best solutions was given by BowerR64. You can consult on the following page: http://www.fixya.com/problems-solutions/t103443,p294056/Canon-PowerShot-G2-Digital-Camera.aspx (just copy and paste on the address bar) ;) Regards