Screen freezes with weird lines, system shuts down

[rip]

Specs (it's old and a prebuilt):  Pentium G640T, 2GBx1 RAM DDR3 @ 532Mhz, 500GB Seagate Barracuda HDD (ST500DM002-1BD142), Windows 7

Motherboard: https://support.hp.com/us-en/product/hp-pavilion-p2-1200-desktop-pc-series/5258516/model/5264148/document/c03333871

PSU: none, the power is supplied directly to the motherboard

 

So whenever the screen gives weird lines like this the PC freezes and then I either have to manually force shutdown (holding Power button) or it shuts off then turns on itself back

Then I get to a screen saying whether I want to boot into Safe mode, safe mode with networking... or start windows normally

 

Safe mode or normal mode will result sometime in another crash/restart.

Sometimes it happens and sometimes I will be able to use my computer for a long period of time

 

Event Viewer shows no errors however. The only errors are from my antivirus program which seems irrelevant

Quote

The BkavFwDrv service failed to start due to the following error:
The system cannot find the file specified.

 

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The following boot-start or system-start driver(s) failed to load:
BkavChkUI
BkavCoreLib
BkavSD
SysLib
SysLib0
SysLib1
SysLib2
SysLib3
SysLib4
SysLib5
SysLib6
SysLib7

 

And this which is more irrelevant I guess

Quote

The Windows Update service hung on starting.

 

It could also thermal throttle? But it's not an error, it was under Information level

Quote

Processor 1 in group 0 exposes the following:

3 idle state(s)
9 performance state(s)
0 throttle state(s)

 

I would try straight forward solution first rather than saying I need new components/too old throw it away

 

Pics here in spoiler

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