Putting in new HD into tray but screws don't align. Can I disregard screws?

[Crazy Mad Dog Blade]

It's not wide enough to secure from the sides and bottom holes don't align with the trays bottom holes. Can I still use HD here without it being screwed in? 

[Levent]

Check to see side screws align, I don’t remember screwing in. 3.5” disk through bottom, like ever.

[Crazy Mad Dog Blade]

8 minutes ago, Levent said:

Check to see side screws align, I don’t remember screwing in. 3.5” disk through bottom, like ever.

The holes on the side do align but the HD isn't wide enough to be flush with the sides. 

[Crazy Mad Dog Blade]

25 minutes ago, Levent said:

Check to see side screws align, I don’t remember screwing in. 3.5” disk through bottom, like ever.

If you can see in my second picture. There is a small gap between the HD and sides. 

[Hinjima]

13 minutes ago, Crazy Mad Dog Blade said:

If you can see in my second picture. There is a small gap between the HD and sides. 

Thats fine as long as the screws hold the HDD.

[Godlygamer23]

What chassis is this?

[da na]

Modern HDDs (eg past 5yrs) have been omitting the middle screws which it seems that chassis requires. There just isn't space to put screwholes there on high-platter-count drives. You could use the two front screws and that'd be fine unless the HDD is hanging upside down - else, you'd want to also use side screws if possible.