Optimising BIOS settings for gaming

Your PC is probably leaving performance on the table. Not because of the hardware, but because the BIOS shipped with settings designed for broad compatibility, not for getting the most out of your components. These are the changes worth making.

1. Enable XMP / EXPO for your RAM

This is the single biggest free performance gain most systems are missing. By default, your motherboard runs RAM at a safe baseline speed, often 2133MHz or 2400MHz, regardless of what your kit is rated for. If you bought 3600MHz RAM, you're not getting 3600MHz until you turn this on.

In your BIOS, look for XMP (Intel) or EXPO (AMD). It's usually under an AI Overclock Tuner, Memory Profile, or similar menu. Select Profile 1 and save. Games that are CPU-bound - open world titles, strategy games, anything with lots of NPCs - will see a measurable uplift.

2. Set your CPU power limits

Manufacturers cap CPU power delivery conservatively to stay within thermal and warranty guidelines. If you have decent cooling, you can lift these.

Look for PL1 and PL2 (Intel) or PPT / TDC / EDC (AMD Ryzen). Setting both PL values to their maximum lets your CPU sustain boost clocks for longer instead of throttling back after a few seconds of load. The difference shows up clearly in CPU-heavy titles.

3. Enable Resizable BAR

Resizable BAR lets your CPU access the full GPU frame buffer at once rather than in small chunks. It's a genuine performance uplift in modern titles, typically 5-15% depending on the game.

To enable it, turn on Above 4G Decoding first, then Resizable BAR will appear as a separate option. Both need to be on. Your GPU also needs to support it (most cards from the last four years do), and you may need to update your GPU driver after enabling.

4. Disable unused boot devices

Not a performance setting, but disabling unused boot devices (old USB drives, network boot, optical drive) cuts your POST time and reduces the chance of a stray USB drive causing a failed boot. Fast Boot helps here too.

5. Check your storage mode

If your boot drive is an NVMe SSD and your BIOS storage mode is set to IDE or AHCI, you're losing NVMe's full speed advantage. Make sure your NVMe slot is set to NVMe or PCIe mode, not emulating an older interface.

Some BIOSes default new M.2 slots to SATA compatibility mode even when a PCIe drive is installed, so it's worth checking.

6. Set your fan curves

Setting aggressive fan curves in the BIOS means your system cools itself properly under load without relying on the manufacturer's conservative defaults. Most gaming BIOSes have a visual curve editor. Ramp fans up sharply once temps hit 70°C, and run quietly below 50°C.

When to stop and send it in

If you're hitting instability after any of these changes - crashes, blue screens, POST failures - the most likely culprit is XMP pushing marginal memory traces too hard, or power limit changes exposing a VRM that can't sustain the load. Both are diagnosable on the bench.

If your PC isn't POSTing at all after a BIOS change, clearing CMOS (a jumper on the motherboard, or removing the CMOS battery for 30 seconds) will reset everything to defaults. If it still won't POST after that, bring it in - we can diagnose and recover from corrupted BIOS, dead CMOS batteries, and VRM issues at component level.