GPU inquiry: Power provided by the pcie slot.

[ytszazu]

Hello there,

Kindly requesting some advice for a newbie over-clocker here.

I have a HD 7750 connected to a pcie slot via a riser cable.

Initial: 880 Mhz 1.2 V 1125 Mhz memory
Max stable overclock: 1050 Mhz 1.3 V 1330 Mhz memory
Power consumption is set to adjustable at 45 W +- 90%.

This GPU does not have 6-pin.

When I adjusted the voltage to 1.35V (Max +90% power), the fps went lower, I suspect it hit either the gpu power supply wattage setting (1.35 V vs 1.3V theoretically allows for less amps for hitting a target watt limit) or no more additional current available from the pcie slot.

My question is:

1) Why the fps went lower when the voltage went from 1.3V to 1.35V?

2) I shot a temperature gun at the components at the gpu and motherboard near the pcie slot, and I couldn't find anything above 70C for the gpu or above 50C for the motherboard components near the pcie slot. Which components on the motherboard pcie line I need to worry if i am drawing too much power from it?

3) Generally, the pcie slot can power up to 75 Watts. Is it beneficial to adjust from 45W +- 90% to example 55W +-90% ?

4) Is there a hard-volt mod to connect some external power to the gpu?

Thank you,

Regards,

ytszazu

 

[EarthDog]

1. Wasn't stable... possibly hitting the power limit on the card...?
2. The slot itself. But a temp gun isn't going to tell you anything.
3. Not sure what this means...
4. Doubt it... and it wouldn't be worth the performance increase.

 

[stompah]

If there was a mod to add extra voltage to the card are you certain it would solve your problem?

Here is someone with a successful volt mod. But dissimilar to what you are looking to do.

Would it be easier and safer to rather than spend money and time to do a volt mod sell this current card and buy something a generation newer? Something like an r9 270, 270x or 280.

 

[ytszazu]

Thank you for your advice and the link.

Prices in the second hand market is not attractive at the moment now through.