Are all IDE Hard Drives similar for fit?

I'm going to have replace my HD really soon. I have a 3 year old eMachine.
I understand I need a IDE or PATA drive. Is there a difference between a laptop and a tower drive if both are listed as IDE drives? I wan the cheapest thing I can get for now. Don't want to put a lot into my system since I want to switch to a lap top in the next few months.

 

You've got it a little bit backwards there

Standard desktop hard drives are 3.5", and laptop drives are 2.5" (9mm).

Most drives in a desktop tower go into 3.5" bays (same size where floppy drives go). There are adapter kits to fit a 3.5" drive in a 5.25" bay.

 

Thanks very much. I will look for the 5.25 inch. I had no idea about the size difference. I think my eMachines computer will take whatever is the most common.

 

Wait, there seems to be a mis-understanding here. plodr's comments are a bit mis-leading. You won't find a 5.25 inch IDE hard drive. Standard computer cases have 5.25 inch "bays" but those are for CD and DVD drives.

The standard size hard drive for a desktop/tower computer is 3.5 inch. Hard drives don't even come in 5.25 inch size. However, they can be mounted in 5.25 inch bays by using spacer brackets to secure them in place. But, if you have an open 3.5 inch bay, it should be the first choice for a parking spot for your 3.5 inch hard drive.

 

well thats Not completely true as far as the HDd operation is concerned you Don't need to buy mounting brackets Just Put Is some where in the case thats level and hold It IN place with something IE (Duct tape ect ect ) but If your going to be moving your tower around or Picking it up U don't what to have the HDD moving around

BTW 5.5 Drive ARE VERY OLD Tec 3.5 Inc are standard in desktops and a 2.5 laptop Driver should work In a desktop
btw make backup of your Import'n files Before poking around Changeling a HDD drive In case something Go's Wrong U will have a back up

 

Yes, you could do that, but it's not a good idea.

I don't know whether this is still the case but hard drive makers used to commonly include mounting brackets for mounting 3.5 inch drives in 5.25 inch bays, with any retail packaged hard drive.