Upvote:2
I'd suggest taking it in your hand luggage (if it'll fit in the dimensions).
My main concern about putting a PC into your checked luggage would be a) it getting broken, or b) it getting stolen. The airline's liability for lost or stolen luggage is relatively low - perhaps below the cost of your PC. Even if it's not, then you do face the hassle of replacement - and of convincing them that the damage to your fragile item was their fault.
I have, however, taken a small form factor PC in hand luggage before (on Malaysia Airlines as it happens, in 2015). It was in a dodgy looking black holdall and no-one batted an eyelid, either in London or when I changed planes and recleared security in Kuala Lumpur.
In case they asked me to switch it on (they didn't), I brought a power lead, and I think a couple of bits like a keyboard. I arrived 3 hours early just in case they wouldn't let it go in hand luggage and forced me to check it in. The thumbscrews on the case would have allowed me to open it up if need be - don't bring a screwdriver!
Unfortunately my experience is only anecdotal. But at least it's one data point for you.
And with regard to the hard drives - no-one at airport security is likely to care what's on the hard drives. Malaysian customs could theoretically care - you're not allowed to bring in anything p**nographic or seditious, but then you're probably not allowed that in Saudi Arabia either.