Since it sounds like there is now no GPU fan, it's proper for it to overheat.
What do you mean by "cartridges"?
So, I recently took apart my computer and replaced the thermal paste on the cpu and gpu. I was very careful when doing this. I put a pea size glob of thermal compound on the heat sink and lined it up with the card first try with barely any sliding(maybe a fraction of an inch) and screwed it in right away. I feel like I didn't allow any way for air bubbles to get in the paste The gpu fan went bad and I took it off, but after turning on my computer the graphics card is now overheating even worse. There's no room for a fan near it(it's simply not an option. There's not really even room in the case for a newer graphics card(as most of the ones I've looked into come as cartridges and not just board/card).
So, I can turn the computer on and I can play VERY low-req games(runescape is the only one so far lol), but if I start anything more intensive(even like kotor 2/terraria) the computer starts getting choppy and the card heats up to upwards of 100C(yes I know that is VERY bad), so playing games is my an option at present. Any ideas on what might be wrong? Is it just that there's no fan? Did I maybe mess the thermal paste up somehow?

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