I replaced my old HDD with a new SSD recently. However, I found that my computer heats up faster than before. So I wonder does SSD’s fast read/write speed hurts CPU?
SSD enhanced the read/write speed very much which is greatly improving your system performance. As we all know that the CPUs are growing much faster to a high performance which is redundant for our system, but traditional HDD was the shackle of PC before the SSD was born. Now SSD improves the storage transfer rate very much so that it balances the system performance. The SSD will not hurt your CPU since it is way beyond needed level.
As Kamlee hints at, the SSd is unlikely to be the cause of your problem. Check that the fan on the heatsink to the CPU is running, check that you have no build up of dust around the fans and power supply.
Your BIOS or UEFI may well have a page that displays the fan speeds and temperatures, check whether the fan speeds are reasonably constant in speed. If they are not set to auto speed sensing it might be an idea to enable this.
Depending on the age of your motherboard and whether your PC is kept in hot conditions and is on 24 hours or long periods, you should visually check the capacitors on your motherboard and see if any appear to be bulging or ozzing a brown goo from either the top or the bottoms.
The capaictors that you need to look at are round, slim and tallish (may be coloured blue, green or purple) they will have a cross type cut mark on their tops (this is where the bulge will be and caneven be opened if they are becoming unhappy), they will also have eiather a black stripe down one side or a down arrow. The board will have a designator near them which will normally begin with C and a number EG: C80 or C112 etc.
If you only see short aluminium looking ones (will have a blue or black stripe on their tops), it is unlikely that you have any aging capacitors.