First, a reality check. There is no official Street Fighter IV for the Nintendo DS. What you’ll find online are impressive homebrew demakes (most notably Street Fighter IV – Hyper Fighting or fan-made ports based on the Super Street Fighter IV assets) or, in some cases, ROM hacks of Street Fighter Alpha 3 or Ultimate Mortal Kombat with replaced sprites. If you download a file claiming to be “SF4.nds” and it’s 64MB, you’re likely looking at a custom build.
To save your time and PC from malware, here is a blacklist of red flags that indicate a "fix" is a scam:
Despite the facts, the search for "Street Fighter 4 Nds Rom Download Fix" gets over 1,000 monthly searches. Why? Because the Nintendo DS was the king of fighting games (Jump Ultimate Stars, Bleach, Guilty Gear Dust Strikers). Fans wanted Capcom to port SF4. The "fix" they seek is actually nostalgia for a game that was never born. Street Fighter 4 Nds Rom Download Fix
Since you cannot fix a ghost, you need to change your hardware or software target. Here are three guaranteed ways to play Street Fighter IV on a handheld today.
Stop looking for SF4. Play the best native fighting game on the NDS which uses the same 2.5D engine techniques: First, a reality check
If you are a developer or a tinkerer, there is a way to create a playable Street Fighter 4 experience on the NDS, but it requires sacrifice.
The "Sprite Swap" Method:
Result: You will have a demake with laggy controls and no sound, but it will technically run on an R4 card. No pre-made ROM exists for this; you must compile it yourself.
If you insist on using your existing NDS flashcart (R4, Ace3DS+, etc.), you cannot play NDS files. However, you can install 3DS Forwarders only if your flashcart is running on a 3DS/2DS console. Result: You will have a demake with laggy
The Step-by-Step "Fix" for confused users: