Hello. First time post.
 
I have a Dell Dimension 4600 with the above card for about 4 years now. The card has had its ups and downs for sure.
 
My biggest headache with the card has been how it isn't recognized sometimes on a cold boot. Turn on the computer and it completely boots, but for some reason I get no video. This is a sporadic problem and I have yet to find a root cause. For the times the card does work and I get video, there are no noticeable problems, all functions work. Even warm reboots work fine.
 
For a while I thought it was overheating, but even after letting the card cool down for several hours, the problem still happens, sometimes. I have installed an Arctic Cool fan on the card when the OEM fan blew out.
 
I have a 250w power supply (original) and read somewhere that this card may need a 300w supply to run adequately. Could this be part of the problem? Only other devices installed included DVD-RW drive and sound card.
 
Driver version: Catalyst 6.2 as recommended by ATI for my setup and the problem. Did not help though. MMC version is 9.0.16 I believe. I've tried different drivers as well, never seemed to help and I at least feel this is a true HW issue.
 
Thanks for any help.

Dude it could just be dying on you, I sold my 9500 Pro to my buddy in 2005 for $20.  That's an OOOLLLLDDDDD card.  You should find an AGP X800XL to replace it (if you can find one).  Heck ANY available AGP card will be at least 3 to 10 times more powerful, even the $40 cards.

I forgot to mention your going to need a decent 450w power supply.  I highly recommend getting the corsiar 450w unit from www.newegg.com
 

Could very well be the power supply.  I agree with the other poster 450w+ should cover about any AGP there is.

The 9800 is getting very old and its probably just dying on you.  Time to make some preparations on putting that card out to pasture.

As for replacements the X800 series or there is word of a HD3850 variant.  Because of lack of supply the X800's are often very expensive if you can find them so it may be best to wait on the 3850.

(1)  As previously stated, could be unreliable power (PSU)
(2)  Card could be failing.
 
      Might try reseating the card several times, 3 to 5.  Older cards ( 3 to 5 years) sometimes develop slight oxidation on the contacts, card and socket.  Multiple reseating "rubs" the oxide off.  Had an old ATI card that this happend to.  Subsequently had to do this about once a year.  At work had a rack with 10 plus cards which interfaced with rack mounted computer, every year it would be come intermittent and reseating the cards restored it to operational.  Probably not your problem, but worth a try.

Thanks for all of the replies.  Much appreciated.  The reseating option has worked for me in the past.  I've thought about upgrading the power as well.

Is the floppy power connection plugged into the 9800 PRO?

In the Bios do you have PCI display or AGP first?
Should be AGP.

You may need one of these, when upgrading your PSU, if what you have is proprietary:
 
Dell to ATX Power Supply Converter
http://www.endpcnoise.com/cgi-bin/ [...] lconverter

This would be your best bet http://www.newegg.com/Product/Prod [...] 6814131090
 
Not a bad price and will increase your performance by a large magnitude.
 
Also you will want to get a decent 450w PSU to go with it. Then all you need to do is upgrade the CPU.

As stated before, try re-seating the Radeon 9800. Might as well clean out all the dust inside the case and on the card itself.
 
My Radeon 9800 Pro still works to this day. I gave it and the rest of my old PC to my cousin about 18 months ago.

 
Great post. dirty contacts do cause this problem on older systems. A new clean pencil eraser also cleans contacts good.
 
I ran a 9800Pro on a 250 watt psu for a long time with no problems(15 amps on the 12 volt rail). It only takes 47 watts peak.

nukemaster - thanks for the backup, just a side comment.
 
   Ref pencil eraser - a no no if contacts are gold plated.  I use to use a eraser, until I found out that in the long run it aggravates the problem.  The pencil eraser is to abrasive and rubs the gold plating off and the base metal then oxidizes at a faster rate.  They make a solution ( don't remember the name) that you put on a soft cloth.  There is also a spray for where you can not get at.  A "Soft gum" eraser might work.

well contact cleaner works, but it has a habit of melting the plastics used in cards.
 
I would assume that the eraser would be an issue over long time and many uses, but in this case the card does not work right anyway. Nothing to loose.