MAMEWorld Forums - Hardware - Delayed stuttering in MAME caused by CPU or GPU?

I'm just getting a bit more into MAME again after a few years absence (got a little less interested when my plans to build a cabinet died after realizing there was no way to fit a cabinet into my house). I'm currently messing around with HLSL and love the way it simulates the look of the old CRT monitors on my laptop's LCD screen.

The weird thing is, I'll load up a game in MAME with HLSL on, and for a good while (like the first run-through of the attract mode in games) the game runs full speed like it does with HLSL off. Then, out of nowhere, it will start to stutter and slowdown and the framerate will drop to about 40-50%. If I exit out of a game and go back into a different game, the stuttering remains. If I exit out of MAME entirely then go back in, the game will run fine again until going through a round of the attract mode.

I'm just wondering if this is caused by my CPU speed not being fast enough, not enough RAM, or my GPU not being powerful enough? My system specs are:

Intel T9300 Penryn CPU running at 2.5 GHz.
nVidia 8700M GT video card.
4 GB RAM
Windows Vista 64 bit Home Premium.

I'm somewhat thinking of getting myself a new laptop as this one is 6 years old now and I've certainly gotten my money's worth, but before investing in a new laptop I was wondering what causes the stuttering I'm seeing after some time in a game (doesn't matter what game I run), and where I should invest more money in the future; the CPU or the GPU?

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