Is the ATI X700 Pro PCI Express Graphics Card compatible in a Dell
Demension E510 computer? If it is will the power supply support it?

You can upgrade to an Ati X700 pci exress card on the system since it
has a pci express slot. most dell systems only came with 200w PSU so
you might need to upgrade your power supply to 300-450w PSU

Hi,p51tony 
  I am agree with cypher0525's answer.

I need to know if the power supply in Dell Demension E510 will support
the ATI X700 PCI Express Card. I have the low end E510 that Dell sells
for $599.00. No other extra cards or devices are installed.

i think the power supply that came with your computer would be 200w
only. so i suggest for you to upgrade the power supply

if you need a high performance and reliable power supply, i'd go for the
enermax EG701AX-VE(W), this is the one that i'm using right now and
never had any problems at all.  this  power supply is recommend for
users who want to overclock their system and for gamers as well.
http://www.tomshardware.com/2005/02/28/strong_showing/page8.html

but since you said that you don't have any other pci cards installed
on the system. a 350w power supply unit would suffice. you could go
for enermax, cooler master, antec, thermaltake. i dont really suggest
for you to get a cheap psu since they dont really last long.

regards,
cypher0525

I own a Dell E510, and I can confirm the usage of an ATI x700.  I've
used one and it works great.  You also might want to note that the
E510 has the option to include an x600, which is nearly as good.

I also own a Dimension E510. Mine has an 256MB X600 so I don't see why
an X700 wouldn't work just the same.

http://reviews.cnet.com/Dell_Dimension_E510/4507-3118_7-31555136.html?tag=sub

That shows the complete specifications of that computer (defaults I'm
guessing). It shows a 305Watt Power Supply. Keep in mind that if it
says you need a 300Watt, it probably isn't a good idea to actually do
it.

DO NOT UPGRADE USING A STANDARD ATX POWER SUPPLY OR YOU WILL DESTROY COMPONENTS!!!

PC Power & Cooling provides upgrades for Dell computers.
http://www.pcpowercooling.com/products/viewproduct.php?show=S47D

If you want to upgrade the PSU, try there first.